Charles Ellicott Commentary Psalms 39:3

"My heart was hot within me; While I was musing the fire burned: [Then] spake I with my tongue:" — Psalms 39:3 (ASV)

The fire burned.—The attempt at repression only makes the inward flame of feeling burn the more fiercely, until at last it is too much for the resolution that has been formed, and the passion of the heart breaks out in words. Like the modern poet, the Hebrew bard had felt

“It would be better not to breathe or speak
Than cry for strength, remaining weak,
And seem to find, but still to seek.”

But thought is too much for him, and he breaks into speech—not, however, fretfully, still less with bitter invective against others. It is a dialogue with the ruler of destiny, in which frail man wants to face his condition, and know the worst.