To the beginning-Christian-believer novice, and even some experienced and seasoned saints in the Lord, the seemingly-contradictory and apparently-conflicting mandates and admonitions regarding human-behavior motivations and functioning pertaining to whether or not to "labor" on "the Sabbath Day" is troubling - to say the least:

On one hand:

Exodus 16:26 Six days you shall gather it; but on the seventh day, which is a sabbath, there will be none." 20:9 Six days you shall labor, and do all your work;
23:12 "Six days you shall do your work, but on the seventh day you shall rest; that your ox and your [farm tractor or donkey or 18-wheeler or whatever] may have rest, and the son of your bondmaid, and the alien, may be refreshed.

Numbers 15:32 While the people of Israel were in the wilderness, they found a man gathering sticks on the sabbath day.
33 And those who found him gathering sticks brought him to Moses and Aaron, and to all the congregation.
34 They put him in custody, because it had not been made plain what should be done to him.
35 And the LORD said to Moses, "The man shall be put to death; all the congregation shall stone him with stones outside the camp."
36 And all the congregation brought him outside the camp, and stoned him to death with stones, as the LORD commanded Moses. [sounds like sharia law?]

Exodus 31:14 You shall keep the sabbath, because it is holy for you; every one who profanes it shall be put to death; whoever does any work on it, that soul shall be cut off from among his people.
Exodus 34:21 "Six days you shall work, but on the seventh day you shall rest; in plowing time and in harvest you shall rest.

Deuteronomy 5:13 Six days you shall labor, and do all your work;
Deuteronomy 16:8 For six days you shall eat unleavened bread; and on the seventh day there shall be a solemn assembly to the LORD your God; you shall do no work on it.

Nehemiah 10:31 and if the peoples of the land bring in wares or any grain on the sabbath day to sell, we will not buy from them on the sabbath or on a holy day [liquor stores, Walmart, gas stations, and similar commercial sellers will have to wait]; and we will forego the crops of the seventh year and the exaction of every debt.

Nehemiah 13:15 In those days I saw in Judah men treading wine presses on the sabbath, and bringing in heaps of grain and loading them on asses; and also wine, grapes, figs, and all kinds of burdens, which they brought into Jerusalem on the sabbath day; and I warned them on the day when they sold food.
16 Men of Tyre also, who lived in the city, brought in fish and all kinds of wares and sold them on the sabbath to the people of Judah, and in Jerusalem.
19 When it began to be dark at the gates of Jerusalem before the sabbath, I commanded that the doors should be shut and gave orders that they should not be opened until after the sabbath. And I set some of my servants over the gates, that no burden might be brought in on the sabbath day.
21 But I warned them and said to them, "Why do you lodge before the wall? If you do so again I will lay hands on you." From that time on they did not come on the sabbath.

Jeremiah 17:21 Thus says the LORD: Take heed for the sake of your lives, and do not bear a burden on the sabbath day or bring it in by the gates of Jerusalem.
22 And do not carry a burden out of your houses on the sabbath or do any work, but keep the sabbath day holy, as I commanded your fathers.
24 "'But if you listen to me," says the LORD, "and bring in no burden by the gates of this city on the sabbath day, but keep the sabbath day holy and do no work on it,
25 then there shall enter by the gates of this city kings who sit on the throne of David, riding in chariots and on horses, they and their princes, the men of Judah and the inhabitants of Jerusalem; and this city shall be inhabited for ever.
26 And people shall come from the cities of Judah and the places round about Jerusalem, from the land of Benjamin, from the Shephelah, from the hill country, and from the Negeb, bringing burnt offerings and sacrifices, cereal offerings and frankincense, and bringing thank offerings to the house of the LORD.
27 But if you do not listen to me, to keep the sabbath day holy, and not to bear a burden and enter by the gates of Jerusalem on the sabbath day, then I will kindle a fire in its gates, and it shall devour the palaces of Jerusalem and shall not be quenched.'"

Amos 8:5 ....."When will the new moon be over, that we may sell grain? And the sabbath, that we may offer wheat for sale, that we may make the ephah small and the shekel great, and deal deceitfully with false balances..."

But....and VERY mysteriously on the other hand....the apparent complete opposite is intended by Jesus Christ, the Colossians-chapter-one-and-Hebrews-chapter-one-identified Creator God, who apparently morphs into seemingly-inconsistent Rule-ChangerJesus of Nazareth:

Matthew 12:8 For the Son of man is Lord of the sabbath."
Luke 6:5 And He said to them, "The Son of man is Lord of the sabbath."

Such is not the ONLY case of apparent doctrinal inconsistency, being that while the Old-Testament Torah strictly forbids ingesting blood (though not roasted well-done cooked flesh):

Leviticus 7:26 Moreover you shall eat no blood whatever, whether of fowl or of animal, in any of your dwellings.
Leviticus 7:27 Whoever eats any blood, that person shall be cut off from his people."

Leviticus 17:14 "For the life of every creature is the blood of it; therefore I have said to the people of Israel, You shall not eat the blood of any creature, for the life of every creature is its blood; whoever eats it shall be cut off.

...yet it seems that Jesus commanded His perhaps-quite-confused-possibly-also-ickened disciples and followers do do the very opposite:

Matthew 20:22 But Jesus answered, "You do not know what you are asking. Are you able to drink the cup that I am to drink?" They said to him, "We are able."
Matthew 20:23 He said to them, "You will drink My cup, but to sit at My right hand and at My left is not mine to grant, but it is for those for whom it has been prepared by My Father."
Matthew 26:42 Again, for the second time, He went away and prayed, "My Father, if this cannot pass unless I drink it, Your will be done."

Mark 10:38 But Jesus said to them, "You do not know what you are asking. Are you able to drink the cup that I drink, or to be baptized with the baptism with which I am baptized?"

John 18:11 Jesus said to Peter, "Put your sword into its sheath; shall I not drink the cup which the Father has given Me?"

[ NOTE: It obviously seems that Jesus is referring to some planned project rather than actually drinking(?) some porcelin or alabaster cup in the passages above. Even though He is clearly referring to some actual and real intended activity, it is logical to assume (and not presume) that He is speaking symbolically, allegorically, metaphorically, or euphemistically ]

And how about the following passage where Jesus and the Samaritan woman were alone together at some watering hole?

John 4:9 The [five-husbands] Samaritan woman said to Him, "How is it that you, a Jew, ask a drink of me, a woman of Samaria?" For Jews have no dealings with Samaritans [are we talking titty milk here from the town floozie?].
John 4:10 Jesus answered her, "If you knew the gift of God, and who it is that is saying to you, 'Give me a drink,' you would have asked Him, and He would have given you living water [referring to jacked-off semen during quickie oral-sex fellatio?]."

It happened again later on:

John 7:37 On the last day of the feast, the great day, Jesus stood up and proclaimed, "If any one thirst, let him come to Me and drink. [A general-public homosexual-proclamation proposition?]

Reading on in the context leaves sexually-oriented suppositions as to the real meaning and liquid involved with reference to the word "drink" in the dust.

Now, we get to the red meat of the apparent contradiction against the Old-Testament 'NEVER eat ANY blood' warnings, and such apparently insane absurdity is found ONLY in the 6th chapter of the gospel of John:

John 6:48 I am the bread of life [sounds like a tasty euphemism, but whether whole wheat or rye or pumpernickel is not known].
49 Your fathers ate the manna [yum!] in the wilderness, and they died [pity].
50 This is the bread which comes down from heaven, that a man may eat of it and not die. [What in the duce was He referring to?]
51 I am the living [?] bread which came down from heaven; if any one eats of this bread, he will live for ever; and the bread which I shall give for the life of the world is My flesh." [Oh Oh]
52 The Jews then disputed among themselves, saying, "How can this man give us his flesh to eat?" [Holy Cannibalism!]
53 So Jesus said to them, "Truly, truly, I say to you, unless you eat the flesh of the Son of man and drink Mis blood [double yuck!], you have no life in you;
54 he who eats My flesh and drinks My blood [has long is He going to keep THAT up?] has eternal life, and I will raise him up at the last day.
55 For My flesh is food indeed, and My blood is drink indeed ]Oh ish!].
56 He who eats My flesh and drinks My blood [I'm getting nauseated!] resides in me, and I in him.
57 As the living Father sent Me, and I live because of the Father, so he who eats Me [Gross!] will live because of Me.
58 This is the bread which came down from heaven, not such as the fathers ate and died; he who eats this bread will live for ever." [A religious mentally-challenged wackjob nutcase? Call 911.]
59 This He said in the synagogue, as He taught at Capernaum [Where is the nearest mental hospital and ambulance?].
60 Many of His disciples, when they heard it, said, "This is a hard saying; who can listen to it?" [THAT is The Understatement of The Year!]
61 But Jesus, knowing in himself that His disciples murmured at it, said to them, "Do you take offense at this? [Duh!]
62 Then what if you were to see the Son of man ascending where He was before? [And what, for Pete's sake, has THAT to do with blood-slurping?]
63 It is the spirit that gives life, the flesh is of no avail; the words that I have spoken to you are spirit and life. [Ohhhhhhh. NOW we get it! Holy Eucharistic Euphemism!]

Matthew 26:29 I tell you I shall not drink again of this fruit of the vine [beats the heck out of drinking? cups of alabaster or porcelin....let alone human blood!] until that day when I drink it new with you in My Father's kingdom." Mark 14:25 Truly, I say to you, I shall not drink again of the fruit of the vine [Intoxicating, or not? At least He is finally off the drinking-human-blood kick!] until that day when I drink it new in the kingdom of God." And now, notice that that ABSOLUTELY-NO-work-on-the-Sabbath thing is starting to unravel, first by describing the work of guard duty on the Sabbath:

Numbers 28:9 "On the sabbath day two male lambs a year old without blemish, and two tenths of an ephah of fine flour for a cereal offering, mixed with oil, and its drink offering:

Second Kings 11:9 The captains did according to all that Jehoiada the priest commanded, and each brought his men who were to go off duty on the sabbath, with those who were to come on duty on the sabbath, and came to Jehoiada the priest.

Second Chronicles 23:4 This is the thing that you shall do: of you priests and Levites who come off duty on the sabbath, one third shall be gatekeepers,
Second Chronicles 23:8 The Levites and all Judah did according to all that Jehoiada the priest commanded. They each brought his men, who were to go off duty on the sabbath, with those who were to come on duty on the sabbath; for Jehoiada the priest did not dismiss the divisions.

Ezekiel 46:1 "Thus says the Lord GOD: The gate of the inner court that faces east shall be shut on the six working days; but on the sabbath day it shall be opened and on the day of the new moon it shall be opened.
Ezekiel 46:4 The burnt offering that the prince offers to the LORD on the sabbath day shall be six lambs without blemish and a ram without blemish;
Ezekiel 46:12 When the prince provides a freewill offering, either a burnt offering or peace offerings as a freewill offering to the LORD, the gate facing east shall be opened for him; and he shall offer his burnt offering or his peace offerings as he does on the sabbath day. Then he shall go out, and after he has gone out the gate shall be shut.

Obviously it looks like clergy ARE allowed to work as long as it is mostly limited to preaching (i.e. teaching) and healing [plus occasionally rubbing grains together by hand in a grainfield, pallet-carrying, pulling donkeys out of pits or changing a flat tire if one does not have AAA towing] on "the Sabbath" for [or to get to?] church services....which clearly was something hard-ass nitpicky made-up-their-own-legalistic-rules pharisees did not comprehend:

Matthew 12:1 At that time Jesus went through the grainfields on the sabbath; His disciples were hungry, and they began to pluck heads of grain and to eat.
2 But when the Pharisees saw it, they said to Him, "Look, your disciples are doing what is not lawful to do on the sabbath."
3 He said to them, "Have you not read what David did, when he was hungry, and those who were with him:
4 how he entered the house of God and ate the bread of the Presence [special toast groovier than communion wafers?], which it was not lawful for him to eat nor for those who were with him, but only for the priests?
5 Or have you not read in the law how on the sabbath the priests in the temple profane the sabbath, and are guiltless?
6 I tell you, something greater than the temple is here.
7 And if you had known what this means, 'I desire mercy, and not sacrifice,' you would not have condemned the guiltless.

Matthew 12:10 And hey, there was a man with a withered hand. And they asked Him, "Is it lawful to heal on the sabbath?" so that they might accuse Him.
11 He said to them, "What man of you, if he has one sheep and it falls into a pit on the sabbath, will not lay hold of it and lift it out?
12 Of how much more value is a man than a sheep! So it is lawful to do good on the sabbath."

Mark 1:21 And they went into Capernaum; and immediately on the sabbath He entered the synagogue and taught.
Mark 2:24 And the Pharisees said to him, "Look, why are they doing what is not lawful on the sabbath?"
Mark 3:2 And they watched Him, to see whether He would heal him on the sabbath, so that they might accuse Him. {Haven't they something better to do, like spy on XXX-rated women caught in the acts of adultery?]
Mark 3:4 And He said to them, "Is it lawful on the sabbath to do good or to do harm, to save life or to kill?" But they were silent.
Mark 6:2 And on the sabbath He began to teach in the synagogue; and many who heard him were astonished, saying, "Where did this man get all this? What is the wisdom given to Him? What mighty works are wrought by His hands!
Mark 2:24 And the Pharisees said to Him, "Look, why are they doing what is not lawful on the sabbath?"

Luke 4:16 And he came to Nazareth, where He had been brought up; and He went to the synagogue, as His custom was, on the sabbath day. And He stood up to read;
Luke 4:31 And he went down to Capernaum, a city of Galilee. And He was teaching them on the sabbath;

Luke 6:2 But some of the Pharisees said, "Why are you doing what is not lawful to do on the sabbath?"
Luke 6:7 And the scribes and the Pharisees watched Him, to see whether He would heal on the sabbath, so that they might find an accusation against him.
Luke 6:9 And Jesus said to them, "I ask you, is it lawful on the sabbath to do good or to do harm, to save life or to destroy it?"

Luke 13:10 Now He was teaching in one of the synagogues on the sabbath.
Luke 13:14 But the ruler of the synagogue, indignant because Jesus had healed on the sabbath, said to the people, "There are six days on which work ought to be done; come on those days and be healed, and not on the sabbath day." [Call the cops.]
Luke 13:15 Then the Lord answered him, "You hypocrites! [Tards!] Does not each of you on the sabbath untie his ox or his ass from the manger, and lead it away to water it?
Luke 13:16 And ought not this woman, a daughter of Abraham whom Satan bound for eighteen years, be loosed from this bond on the sabbath day?"

Luke 14:3 And Jesus spoke to the lawyers and Pharisees, saying, "Is it lawful to heal on the sabbath, or not?" Luke 23:56 then they returned, and prepared spices and ointments. On the sabbath they rested according to the commandment [back to the good-ol' No-work-whatsoever-on-the-Sabbath Torah days!].

John 5:10 So the Jews said to the man who was cured, "It is the sabbath, it is not lawful for you to carry your pallet."
11 But he answered them, "The man who healed me said to me, 'Take up your pallet, and walk.'"
12 They asked him, "Who is the man who said to you, 'Take up your pallet, and walk'?" [Assemble the hit squad.]
13 Now the man who had been healed did not know who it was, for Jesus had withdrawn, as there was a crowd in the place.
14 Afterward, Jesus found him in the temple, and said to him, "See, you are well! Sin no more, that nothing worse befall you."
15 The man went away and told the Jews that it was Jesus who had healed him. [Shame!]
16 And this was why the Jews persecuted Jesus, because He did this on the sabbath. [Naughty Naughty]
17 But Jesus answered them, "My Father is working still, and I am working."
18 This was why the Jews sought all the more to kill Him, because He not only broke the sabbath but also called God his Father, making himself equal with God.
19 Jesus said to them, "Truthfully, I say to you, the Son can do nothing of His own accord, but only what He sees the Father doing; for whatever He does, that the Son does likewise.
20 For the Father loves the Son, and shows him all that he himself is doing; and greater works than these will he show him, that you may marvel.
21 For as the Father raises the dead and gives them life, so also the Son gives life to whom He will.
22 The Father judges no one, but has given all judgment to the Son,
23 that all may honor the Son, even as they honor the Father. He who does not honor the Son does not honor the Father who sent him.

John 7:22 Moses gave you circumcision - not that it is from Moses, but from the fathers - and you circumcise a man [though, again, NOT any woman? The Greek Text word is: anthr(o)pon -- which strange word, under the apparent gender-specific circumstances -- is explained in the next verse] upon the sabbath.
7:23 If on the sabbath a "man" [sexist exclusion against women...or instead physical impossibility - concerning dongs-absent female humans? Thank God women can be saved without impossible-for-them penile circumcisions? The Greek Text word is: anthr(o)pos....and no matter WHAT the ending is of the Greek-lettered root word, it always refers to EITHER gender! Weird, huh?] receives circumcision, so that the law of Moses may not be broken, are you angry with me because on the sabbath I made a man's whole body well?

John 9:16 Some of the Pharisees said, "This man [Gr. anthr(o)pos] is not from God, for He does not keep the sabbath." But others said, "How can a man [Gr. anthr(o)pos...and absolutely fascinating the choice of either-gender Greek word, isn't it] and who is a sinner do such signs?" There was a division among them.

[ NOTE: But please, no homogay-"artist" pics nor paintings of Jesus with effeminate loose long hair. Why self-sodomizingly masturbate? ]

The subject of whether or not "the Sabbath" should generally be regarded as "Sunday" instead of "Saturday" according to the rather-universally-accepted Gregorian Calender...is somewhat of a moot point....especially relating to national-security guard-duty rotation:

Romans 14:5 One man esteems one day as better than another, while another man esteems all days alike. Let every one be fully convinced in his own mind.

Hopefully, we all (including this webpage author having researched all this) have a better understanding of the paradox of two almost-irreconcilable premises on this subject within Holy Writ.