John Calvin Commentary Psalms 39:12

"Hear my prayer, O Jehovah, and give ear unto my cry; Hold not thy peace at my tears: For I am a stranger with thee, A sojourner, as all my fathers were." — Psalms 39:12 (ASV)

Hear my prayer, O Jehovah! David gradually increases his vehemence in prayer. He speaks first of prayer; in the second place, of crying; and in the third place, of tears. This gradation is not a mere rhetorical figure, serving only to adorn the style or to express the same thing in different words. This shows that David lamented his condition sincerely and from the bottom of his heart; and in this, he has given us, by his own example, a rule for prayer.

When he calls himself a stranger and a sojourner, he again shows how miserable his condition was. He adds expressly, before God, not only because humans are absent from God as long as they dwell in this world, but also in the same sense in which he formerly said, My days are before thee as nothing. This means that God, without needing anyone to inform Him, knows full well that humans have only a short journey to make in this world, the end of which is soon reached, or that they remain only a short time in it, like temporary lodgers. The substance of the Psalmist’s discourse is that God sees from heaven how miserable our condition would be if He did not sustain us by His mercy.