The iniquity of my heels - Perhaps עקבי akebai, which we translate my heels, should be considered the contracted plural of עקבים akebim, supplanters. The verse would then read thus: "Wherefore should I fear in the days of evil, though the iniquity of my supplanters should compass me about." The Syriac and Arabic have taken a similar view of the passage: "Why should I fear in the evil day, when the iniquity of my enemies compasses me about." And so Dr. Kennicott translates it.
Wherefore should I fear in the days of evil - This verse is designed evidently to state the main subject of the psalm; the result of the reflections of the author on what had been to him a source of perplexity; on what had seemed to him to be a dark problem. He “had” evidently felt that there was occasion to dread the power of wicked rich men; but he now felt that he had no ground for that fear and alarm. He saw that their power was short-lived; that all the ability to injure, arising from their station and wealth, must soon cease; that his own highest interests could not be affected by anything which they could do. The “days of evil” here spoken of are the times which are referred to in the following phrase, “when the iniquity of my heels,” etc.
When the iniquity of my heels shall compass me about - It would be difficult to make any sense out of this expression, though it is substantially the same rendering which is found in the Vulgate and the Septuagint. Luther renders it “when the iniquity of my oppressors encompasses me.” The Chaldee Paraphrase renders it, “why should I fear in the days of evil, unless it be when the guilt of my sin compasses me about?” The Syriac renders it, “the iniquity of “my enemies.” The Arabic, “when my enemies surround me.” DeWette renders it as Luther does. Rosenmuller, “when the iniquity of those who lay snares against me shall compass me around.” Prof. Alexander, “when the iniquity of my oppressors (or supplanters) shall surround me.” The word rendered “heels” here - עקב ‛âqêb - means properly “heel,” Genesis 3:15; Job 18:9; Judges 5:22; then, the rear of an army, Joshua 8:13; then, in the plural, “footsteps,” prints of the heel or foot, Psalm 77:19; and then, according to Gesenius (Lexicon) “a lier in wait, insidiator.”
Perhaps there is in the word the idea of craft; of lying in wait; of taking the advantages - from the verb עקב ‛âqab to be behind, to come from behind; and hence to supplant; to circumvent. So in Hosea 12:3, “in the womb he held his brother by the heel” (compare Genesis 25:26). Hence, the word is used as meaning to supplant; to circumvent, Genesis 27:36; Jeremiah 9:4 (Hebrew, Jeremiah 9:3) This is, undoubtedly, the meaning here. The true idea is, when I am exposed to the crafts, the cunning, the tricks, of those who lie in wait for me; I am liable to be attacked suddenly, or to be taken unawares; but what have I to fear? The psalmist refers to the evil conduct of his enemies, as having given him alarm. They were rich and powerful. They endeavored in some way to supplant him - perhaps, as we should say, to “trip him up” - to overcome him by art, by power, by trick, or by fraud. He “had” been afraid of these powerful foes; but on a calm review of the whole matter, he came to the conclusion that he had really no cause for fear. The reasons for this he proceeds to state in the following part of the psalm.