Making stupid promises or vows. Are we bound by them?

Matthew 14:1-12(NKJV)

At that time Herod the tetrarch heard the report about Jesus 

and said to his servants, “This is John the Baptist; he is risen from the dead, and therefore these powers are at work in him.” 

For Herod had laid hold of John and bound him, and put him in prison for the sake of Herodias, his brother Philip’s wife. 

Because John had said to him, “It is not lawful for you to have her.” 

And although he wanted to put him to death, he feared the multitude, because they counted him as a prophet.

But when Herod’s birthday was celebrated, the daughter of Herodias danced before them and pleased Herod. 

Therefore he promised with an oath to give her whatever she might ask.

So she, having been prompted by her mother, said, “Give me John the Baptist’s head here on a platter.”

And the king was sorry; nevertheless, because of the oaths and because of those who sat with him, he commanded it to be given to her. 

So he sent and had John beheaded in prison. 

And his head was brought on a platter and given to the girl, and she brought it to her mother. 

Then his disciples came and took away the body and buried It, and went and told Jesus.

Was the king bound by his vow?  Did he have to follow through with it?  This question has a couple of interesting aspects. 

First let me start with a story.  My friend Chuck's father was a truck driver.  One time they needed to put a new engine in a truck and they needed a part that was maybe $500.  Chuck's dad thought that was too much and said he could just make one himself.  The guy at the parts store mocked him and said he didn't have the skill.

So Chuck's dad spent something like two days and $1,000 to make a part to save $500.  :)  Afterwards he looked at Chuck and said "Son, don't ever let your pride get in the way of common sense and a smart financial decision."  :)
 

What stopped the king from simply saying "look, what are asking for is unreasonable and I won't do it.  Pick something else."?  I think it was pride.  He says it was because of the oaths and because of who sat with him….  He didn't want to look bad or weak in front of the others.

There is another aspect of this that occurred to me however.  God has made certain promises and oaths to us and we depend on Him not to change His mind.  What if God found Himself in a situation where He let pride get in the way of common sense?  Should God follow Chuck's Dad's advice and admit to a mistake and change direction or should God stick to His promise so that people are assured that God is the same yesterday, today, and forever? 

Interesting question isn't it?  Something to ponder!