Albert Barnes Commentary Psalms 119:139

"My zeal hath consumed me, Because mine adversaries have forgotten thy words." — Psalms 119:139 (ASV)

My zeal hath consumed me — Margin, “cut me off.” The word that is here translated “consumed” is rendered “cut off” in Lamentations 3:53; Job 23:17; Psalms 54:5; Psalms 88:16; Psalms 94:23; Psalms 101:5; Psalms 143:12; “vanish,”Job 6:17; “destroyed,”Psalms 73:27; 2 Samuel 22:41; Psalms 18:40; Psalms 101:8; Psalms 69:4. It means here that he pined away; that his strength was exhausted; that he was sinking under the efforts he had put forth as expressive of his deep interest in the cause of God and of truth. On the sentiment here expressed, see the notes at Psalm 69:9.

because mine enemies have forgotten thy words — Your law; Your commands. It was not because they were his foes — not because he was endeavoring to destroy them, or to take vengeance on them — but because they were unmindful of God, and of the claims of his law. It is a great triumph that religion gains over a man’s soul, when, in looking on the conduct of persecutors, calumniators, and slanderers — of those who are constantly doing us wrong — we are more grieved because they violate the law of God than because they injure us; when our solicitude is turned from ourselves, and terminates on our regard for the honor of God and his law.

Yet that is the nature of true religion; and this is what we should be able to find in ourselves in such circumstances. A man should doubt the evidence of his personal religion, if all his feelings terminate on the wrong done to himself by the wicked conduct of others; if he has no feeling of solicitude because the law of God has been violated and God has been dishonored. Compare the notes at Psalm 119:136.