Is it necessary to keep the sabbath? Bible Contradictions

This Bible contradiction is from the Skeptic's Annotated Bible.

Verses

Yes.

Exodus 16:29 View context

See, for that the LORD hath given you the sabbath, therefore he giveth you on the sixth day the bread of two days; abide ye every man in his place, let no man go out of his place on the seventh day.

Exodus 20:8 View context

Remember the sabbath day, to keep it holy.

Exodus 31:13-15 View context

Speak thou also unto the children of Israel, saying, Verily my sabbaths ye shall keep: for it [is] a sign between me and you throughout your generations; that [ye] may know that I [am] the LORD that doth sanctify you.

Ye shall keep the sabbath therefore; for it [is] holy unto you: every one that defileth it shall surely be put to death: for whosoever doeth [any] work therein, that soul shall be cut off from among his people.

Six days may work be done; but in the seventh [is] the sabbath of rest, holy to the LORD: whosoever doeth [any] work in the sabbath day, he shall surely be put to death.

Exodus 34:21 View context

Six days thou shalt work, but on the seventh day thou shalt rest: in earing time and in harvest thou shalt rest.

Exodus 35:2 View context

Six days shall work be done, but on the seventh day there shall be to you an holy day, a sabbath of rest to the LORD: whosoever doeth work therein shall be put to death.

Leviticus 19:3 View context

Ye shall fear every man his mother, and his father, and keep my sabbaths: I [am] the LORD your God.

Leviticus 23:3 View context

Six days shall work be done: but the seventh day [is] the sabbath of rest, an holy convocation; ye shall do no work [therein]: it [is] the sabbath of the LORD in all your dwellings.

Numbers 15:32 View context

And while the children of Israel were in the wilderness, they found a man that gathered sticks upon the sabbath day.

Deuteronomy 5:12 View context

Keep the sabbath day to sanctify it, as the LORD thy God hath commanded thee.

Isaiah 56:2 View context

Blessed [is] the man [that] doeth this, and the son of man [that] layeth hold on it; that keepeth the sabbath from polluting it, and keepeth his hand from doing any evil.

No.

Isaiah 1:13 View context

Bring no more vain oblations; incense is an abomination unto me; the new moons and sabbaths, the calling of assemblies, I cannot away with; [it is] iniquity, even the solemn meeting.