First off, let me say that the topic question is directed towards those who take the words of the Bible as infallible and not contradicting.

In the book of Isaiah it says...

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.

Yet in Exodus it is stated...

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.