ABC:Exodus 31

Verse 15, Should We Keep the Sabbath?
Dan Barker of FFRF claims there is a contradiction here and makes the following comments (italicized):

Shall We Keep the Sabbath? Exodus 20:8 Remember the sabbath day, to keep it holy. Exodus 31:15 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. Numbers 15:32 And while the children of Israel were in the wilderness, they found a man that gathered sticks upon the sabbath day. 36 And all the congregation brought him without the camp, and stoned him with stones, and he died; as the LORD commanded Moses. vs. Isaiah 1:13 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. John 5:16 And therefore did the Jews persecute Jesus, and sought to slay him, because he had done these things on the sabbath day. Colossians 2:16 ¶ Let no man, therefore, judge you in meat, or in drink, or in respect of an holy day, or of the new moon, or of the sabbath days:

The FFRF want to focus on the Sabbath rules under the Old Covenant, not the New Covenant which Christians are under (Jeremiah 31:31); ignoring the context of the Sabbath for which it was given, as the Israelite Pharisees did. In doing so, they ignore the principles emphasized in the New Testament by Jesus about the Sabbath, that it was intended primarily for the good of people, not as a burden. (Mk. 2:27) What matters is that the Sabbath be used to do good for others. (Mt. 12:12)

The Sabbath was intended to protect the poor from overwork, not create onerous regulations that govern what everyone can do on a certain day of the week (as the Pharisees viewed it). The Old Testament Covenant, including its rules on the Sabbath, was not kept properly by the Israelites for thousands of years, which is why Jesus brought in the New Covenant which emphasizes the underlying spiritual principles the Sabbath was intended for; protecting and helping mankind while focusing on God.

Verse 17
The EvilBible claims a contradiction exists here and makes the following comments (italicized).

God is tired and rests

Exodus 31:17 It is a sign between me and the children of Israel for ever: for in six days the LORD made heaven and earth, and on the seventh day he rested, and was refreshed.

God is never tired and never rests

Isaiah 40:28 Hast thou not known? hast thou not heard, that the everlasting God, the LORD, the Creator of the ends of the earth, fainteth not, neither is weary? there is no searching of his understanding.

This is actually a really tough claim to address, not because of the passages in question, but because of the subject. If Exodus 31:17 were the only passage on this subject it would be easily addressed, since Exodus 31, as pointed out by Probe Ministries, just says that God rested, not that He was necessarily tired. God may, after all, have only rested to serve as a pattern for later creations such as mankind - Jesus even went so far as to say God made the Sabbath or 7th day of rest for man's benefit:

Mark 2:27 And he said unto them, The sabbath was made for man, and not man for the sabbath:

That being said though, there are actually a number of other passages that mention God being weary including Isaiah 1:14, 7:13, 15:6, 43:24, and Malachi 2:17. Therefore I see two possibilities:

1. Isaiah 40:28 was just referring to physical weariness, which God is never said to be. In each case it refers to God being spiritually grieved or wearied at mankind's sinfulness, rather than actual physical exhaustion. As observed by Probe, "The idea is not that God is 'tired' in the sense of 'fatigued.' Rather, God is weary of holding back His righteous judgment... These are not the words of a being who is tired in the sense of needing rest. These are the words of one who is tired of restraining His righteous judgment."

2. A second possibility may be that the Isaiah 40:28 passage is actually getting mistranslated from the Hebrew. It is the only passage in the entire Bible that I am aware of to be translated as saying God does not get weary, after all. Reading the interlinear does not show any word translated "not" so perhaps the passage should actually read "Have you heard of the everlasting God Jehovah, Creator of the utmost parts of the Earth? Faint and weary, seek wisdom."

Isaiah 40:28 Hast thou not known ? hast thou not heard,  that the everlasting <`owlam> God, <'elohiym> the LORD,  the Creator  of the ends of the earth, <'erets> fainteth  not, neither is weary ? there is no searching of his understanding.

In other words, rather than referring to God, the words could be a directive to those who are faint and weary to seek God's wisdom. Using PowerBible CD, the interlinear does not show any words in the passage translated "not" or "neither" so perhaps those are specific to later manuscripts, an error that crept in? If so, checking the oldest manuscripts for Isaiah such as the Great Isaiah Scroll might reveal that the passage is just being slightly mistranslated, and never said God does not grow weary.