John Calvin Commentary Psalms 56:3

"What time I am afraid, I will put my trust in thee." — Psalms 56:3 (ASV)

In the day that I was afraid, etc. In Hebrew, the words are in the future tense, but they must be understood as past tense. He acknowledges his weakness, in that he felt fear, but denies having yielded to it. Dangers might distress him, but they could not induce him to surrender his hope.

He makes no claim to that lofty heroism which despises danger; and yet, while he admits that he felt fear, he declares his firm resolve to persist in a confident expectation of divine favor. The true proof of faith consists in this: that when we feel the promptings of natural fear, we can resist them and prevent them from gaining undue control.

Fear and hope may seem to be opposite and incompatible emotions; yet, observation proves that hope never gains full sway unless some measure of fear is also present. In a calm state of mind, there is no occasion for hope to be exercised. At such times, hope lies dormant, and its power is shown to its best advantage when we see it lifting the soul out of dejection, calming its turmoil, or soothing its worries.

This was how it manifested itself in David, who feared and yet trusted; he was aware of the greatness of his danger, and yet calmed his mind with the confident hope of divine deliverance.