Psalm 116:1-4, 12-19: Promise Loudly

I love the Lord, for he heard my voice; he heard my cry for mercy. Because he turned his ear to me, I will call on him as long as I live. The cords of death entangled me, the anguish of the grave came over me; I was overcome by distress and sorrow. Then I called on the name of the Lord: “Lord, save me!” What shall I return to the Lord for all his goodness to me?

I will lift up the cup of salvation and call on the name of the Lord. I will fulfill my vows to the Lord in the presence of all his people. Precious in the sight of the Lord is the death of his faithful servants. Truly I am your servant, Lord; I serve you just as my mother did; you have freed me from my chains. I will sacrifice a thank offering to you and call on the name of the Lord. I will fulfill my vows to the Lord in the presence of all his people, in the courts of the house of the Lord—in your midst, Jerusalem.

Praise the Lord. - Psalm 116:1-4, 12-19

It is one thing to make a promise to the Lord and keep it quietly. It is another thing to make a promise to the Lord an keep it loudly. Why does the writer make a point of saying that he will keep his promise so publicly? Twice he says he will "fulfill my vows to the Lord in the presence of all his people" Does he want to brag about how holy he is? How he has God's ear? 

I think that there are two reasons: he wants to celebrate God and he wants to hold himself accountable.

First, he wants to celebrate God. Whatever the circumstances that led to this psalm of praise, it was serious. "the anguish of the grave came over me." But God saved him and he feels in a position where he has nothing to give back to God except his public praise "What shall I return to the Lord for all his goodness to me?" So he decides to praise God.

Second, he wants to hold himself accountable. He could have done this in secret, but then failure to make his sacrifice and praise would have limited consequences. By doing it publicly, he sets up the conditions so that he is incentivized to so what he knows he ought to do. Kind of like taking a class in a subject that you could have learned by self-study. Sure you could have gained the same knowledge, but the environment you place yourself in rewards follow-through. 

So yes, this environment can be selfish but it can also be godly. Will I miss one in order to avoid the other?