Albert Barnes Commentary Psalms 116:2

"Because he hath inclined his ear unto me, Therefore will I call [upon him] as long as I live." — Psalms 116:2 (ASV)

Because he has inclined his ear to me - See the notes at Psalms 5:1. Because he has been gracious to me, and has heard my prayers. This is a good reason for serving God, or for devoting ourselves to him, but it is not the only reason. We ought to worship and serve God whether he hears our prayers or not; whether he sends joy or sorrow; whether we are favored with prosperity, or are sunk in deep affliction. People have worshipped God even when they have had no evidence that he heard their prayers; and some of the most pure acts of devotion on earth are those which come from the very depths of darkness and sorrow.

Therefore will I call upon him as long as I live - Margin, as in Hebrew, “in my days.” Encouraged by the past, I will continue to call upon him in the future. I will retain a firm faith in the doctrine that he hears prayer, and I will express my practical belief in the truth of that doctrine by regular and constant habits of worship. When a man once has evidence that God has heard his prayer, it is a reason why he should always call on him in similar circumstances, for God does not change.