2 Samuel 15:7-8

7Now it came about at the end of 1four years that Absalom said to the king, “Please let me go and pay my vow which I have made to the Lord, in 2Hebron.

8For your servant 3made a vow while I was living in Geshur in Aram, saying, ‘4If the Lord will indeed bring me back to Jerusalem, then I will serve the Lord.’”