'Vowed' in the Bible

Then all the people came to persuade David to eat bread while it was still day; but David vowed, saying, “May God do so to me, and more also, if I taste bread or anything else before the sun goes down.”

Now it came about at the end of forty years that Absalom said to the king, “Please let me go and pay my vow which I have vowed to the Lord, in Hebron.

For your servant vowed a vow while I was living at Geshur in Aram, saying, ‘If the Lord shall indeed bring me back to Jerusalem, then I will serve the Lord.’”