John Calvin Commentary Psalms 55:4

"My heart is sore pained within me: And the terrors of death are fallen upon me." — Psalms 55:4 (ASV)

My heart trembles within me. Here we have additional evidence of the extremity of David’s sufferings. He who uses these words was no soft or effeminate person, but one who had given indubitable proofs of constancy. Nor does he complain merely of the atrocious injuries inflicted on him by his enemies.

He exclaims that he is overwhelmed with terrors, and thus acknowledges that his heart was not insensible to his afflictions. We may learn from this passage, therefore, not only that the sufferings David endured at this time were heavy, but also that the fortitude of the greatest servants of God fails them in the hour of severe trial. We are all good soldiers as long as things go well with us, but when brought into close combat, our weakness soon becomes apparent.

Satan avails himself of the advantage, suggests that God has withdrawn the supports of his Spirit, and instigates us to despair. Of this we have an example in David, who is here represented as struggling with inward fears, as well as a complication of outward calamities, and sustaining a severe conflict of spirit in his application to the throne of God. The expression terrors of death, shows that he was on the verge of sinking unless Divine grace interposed.