In Obama's taking of the oath his office, Part Deux, he was sworn in without his hand on a bible.
That is entirely good and proper. For nowhere in the bible does it instruct us to use the book for cheap theatrics or as a poor man's polygraph. Telling the truth honors God—no more/no less if done with one hand on a manufactured representation of His Word. Telling a lie is rank disobedience to God, but not made the worse by doing so in the presence of a gift from the Gideons.
All sin, Jesus reminds us in the Sermon on the Mount, is a matter of the heart, not of trappings or overt actions. Killing is not required to make you a murderer--anger at your brother is sufficient.
Should I ever become President, I would announce this: Because I am a Christian, I will not take the oath of office with one hand on the bible. The doctrine of my faith informs me that to do so is a meaningless gesture. Let my yes mean yes.