John Gill Commentary Psalms 119:131

"I opened wide my mouth, and panted; For I longed for thy commandments." — Psalms 119:131 (ASV)

I opened my mouth, and panted As a person out of breath does, through walking or running; he stops and pants, and opens his mouth, to draw in air to his relief: or as hungry and thirsty persons pant for food and drink, and open their mouths to receive it, before it can well be brought to them. So the psalmist panted after God, and communion with him; desired the sincere milk of the word; longed for the breasts of ordinances, and even fainted for the courts of the Lord, (Psalms 42:1) (84:2) ;

for I longed for your commandments ; for an opportunity of waiting upon God in the way of his duty; to hear his word, and attend his worship.