John Calvin Commentary Psalms 144:3

"Jehovah, what is man, that thou takest knowledge of him? Or the son of man, that thou makest account of him?" — Psalms 144:3 (ASV)

O Jehovah! what is man, etc. He amplifies the goodness shown by God by instituting a comparison. Having declared how uniquely he had been dealt with, he turns his eyes inward and asks, "Who am I, that God should show me such condescension?" He speaks of man in general; notably, he commends the mercy of God by considering his lowly and abject condition.

In other places he mentions grounds of humiliation of a more personal or private nature — here he confines himself to what has reference to our common nature. And though even in discussing the nature of man there are other reasons he might have specified why he is unworthy of the regard and love of God, he briefly refers to his being like the smoke, and as a shadow. We are left to infer that the riches of the divine goodness are extended to objects altogether unworthy in themselves.

We are warned, when prone at any time to forget ourselves and think we are something when we are nothing, that the simple fact of the shortness of our life should subdue all arrogance and pride.

The Scriptures, in speaking of the frailty of man, encompass whatever is necessarily connected with it. Indeed, if our life vanishes in a moment, what is there stable about us?

We are also taught this truth — that we cannot properly estimate the divine goodness unless we take into consideration our true condition, since we can only ascribe to God what is due to Him by acknowledging that His goodness is bestowed upon undeserving creatures.

The reader may seek further information on this point in Psalm 8, where nearly the same truth is emphasized.