The President started his second term by swearing on a family Bible, a King Bible and a Lincoln Bible, so help us God.
Ironically, inside those Bibles a guy named Jesus told people not to take oaths. Check out Matthew 5:33-37 (New King James Version)
33 "Again you have heard that it was said to those of old, 'You shall not swear falsely, but shall perform your oaths to the Lord.' 34 But I say to you, do not swear at all: neither by heaven, for it is God's throne; 35 nor by the earth, for it is His footstool; nor by Jerusalem, for it is the city of the great King. 36 Nor shall you swear by your head, because you cannot make one hair white or black. 37 But let your 'Yes' be 'Yes,' and your 'No,' 'No.' For whatever is more than these is from the evil one.
I love it when all the hyper-theists want to ascribe the United States to be a country founded on God's will. If the so-called righteous patriots who founded the country were really thinking about what was in the Bible, there would be no oath of office. There certainly would not be a Bible involved in putting forward an oath.
So when any federal, state or local office holder puts one hand in the air and the other on a holy book, it is actually "score one for the evil dude". Our elected officials in our "Judeo-Christian" country are already used to breaking the Word of God to start their public careers. No wonder we look at them as people who will do or say anything to get their way.
There was a great discussion on The Michael Smerconish Show about whether to replace the Bible with a copy of the Constitution as an object to swear on. (He also ran a poll on the topic.) Nowhere in the Constitution does it say that we have to use a Bible or request God's help (although, always a good idea). Smerconish made a point to say the Constitution directly forbids using religion as a condition of public service. They brought out the fact the John Quincy Adams actually used a volume of law to swear upon. The idea is that a swearer swears on something valuable to the swearer.
But nothing really happens with these oaths. Like Meatloaf trying to get to 'Paradise by the Dashboard Light,' he is swearing on his mother's grave. I guess if he violates his vow his mother will rise from the cemetery as some kind of rock and roll zombie?
If someone is going to lie, steal, cheat, and generally be a bad person, an oath just gives them cover. It really doesn't matter if you step into a court of law and swear or affirm you are going to tell the truth. If it turns out you don't tell the full truth, you can go to jail. As an oath does not going to stop a person from lying, it isn't going to stop them from doing time for perjury -- the real deterrent from lying on the stand.
As for the president, if his (or any other office holder's) actions don't match up to being a protector of the Constitution, he can be impeached and do time for it. An oath really does nothing except for the ceremony associated with entering the office.
But the reality is, for this president, at this time, with this Constitution; he has to put his hand up and swear. Yes, it was great ceremony to see a president, hounded by distractors who question his faith, use Bibles from part of an American continuum. It is a powerful symbolism of Lincoln's Bible as a possession of the man who freed slaves from physical bondage; to the MLK Bible, from a man who freed African-Americans from institutional bondage; to the hand of Barack Obama, the man who frees all America from having an upper limit. It doesn't get much better.
But if President Obama did follow the strict teachings of Jesus and not take an oath of office, how long would it take the hyper-theist-uber-patriots to draw up articles of impeachment. As they swear about how this is a Christian country.