Albert Barnes Commentary Psalms 66:14

"Which my lips uttered, And my mouth spake, when I was in distress." — Psalms 66:14 (ASV)

Which my lips have uttered... — Margin, “opened.” The Hebrew word, however — פצה pâtsâh — properly means to tear apart, to rend; and then, to open wide, as the mouth or the throat, for example, as wild beasts do (Psalms 22:13). Then it means to open the mouth in scorn (Lamentations 2:16; Lamentations 3:46); and then, to utter hasty words (Job 35:16).

The idea would be expressed by us with phrases like “to bolt” or “blurt out”; to utter hastily; or, to utter from a heart so full and overflowing that one speaks with very little care for the language employed. It is the fullness of the heart that would be suggested by the word, not a careful choice of expressions. The idea is that the heart was full, and the vows were made under the influence of deep emotion, when the heart was so full that it could not help but speak, and when there was very little attention to the language.

It was not a calm and studied selection of words. Such vows are no less acceptable to God than those made in the most carefully selected language. Much of the most popular sacred poetry in all languages is of this nature; and when it is refined down to the most precise rules of art, it ceases to be popular or to meet the needs of the soul, and is laid aside. The psalmist here means to say that even though these vows were the result of deep feeling — of warm, gushing emotion — rather than of calm and thoughtful reflection, he still had no inclination to disown or repudiate them now. They were made in the depth of feeling — in real sincerity — and there was a firm purpose to carry them out faithfully.

When I was in trouble — This refers to when the people were in captivity, languishing in a foreign land. Vows made in trouble — in sickness, in bereavement, in times of public calamity — should be faithfully performed when health and prosperity visit us again; but, alas, how often they are forgotten!