2 Samuel 15:7-9

7 ¶ And it came to pass after forty years, that Absalom said unto the king, I pray thee, let me go and pay my vow, which I have vowed unto the Lord, in Hebron. 8 For thy servant vowed a vow while I abode at Geshur in Syria, saying, If the Lord shall bring me again indeed to Jerusalem, then I will serve the Lord. 9 And the king said unto him, Go in peace. So he arose, and went to Hebron.