Genesis 28:20, 21 And Jacob vowed a vow, saying, If God will be with me, and will keep me in this way that I go, and will give me bread to eat, an raiment to put on, So that I come again to my father’s house in peace: then shall the Lord be my God.
Jacob responded to the Covenant Promise of God by vowing a vow and declaring that the Lord will be his God. When the Lord promised to be with him, to protect him, and to provide for him, so that he might come home again in peace, then Jacob believed God and swore that he would be with Him, that is, that He will be his God. God keeps His promises, and in faithful response, we vow to keep ours.
It is dangerous and wrong for us to make a vow, swear, or take an oath in uncertain or frivolous matters. ”Swear not at all.” It is sinful then when we break a vow (like Peter). However, there are three cases in which it is right and proper to make a vow: 1) in court, when we are required to swear to tell the truth, 2) in marriage, when we vow to be faithful until death, 3) in church, when we in Confirmation, or Ordination, or other instances, vow to be faithful to the Lord and His Word. God takes vows seriously and expects us to be faithful, to keep, and not break them.
God doesn’t need our vows, but we do, to remind us that we made a commitment, and with God’s help, we will keep it. We remember what God did for us in Christ out of faithful love. Then He leads us to respond in commitment. We renew our vows and seal our commitments every time we hear or read the Gospel, and believe it.