4 “Free among the dead”. In these words our Lord's Person is most clearly shown: for who else is free among the dead but He who though in the likeness of sinful flesh is alone among sinners without sin?...He therefore, “free among the dead,” who had it in His power to lay down His life, and again to take it; from whom no one could take it, but He laid it down of His own free will; who could revive His own flesh, as a temple destroyed by them, at His will; who, when all had forsaken Him on the eve of His Passion, remained not alone, because, as He testifies, His Father forsook Him not; was nevertheless by His enemies, for whom He prayed, who knew not what they did,...counted “as one who has no help; like them that are wounded, and lie in the grave.”
But he adds, “Whom thou dost not yet remember:” and in these words there is to be remarked a distinction between Christ and the rest of the dead. For though He was wounded, and when dead laid in the tomb, yet they who knew not what they were doing, or who He was, regarded Him as like others who had perished from their wounds, and who slept in the tomb, who are as yet out of remembrance of God, that is, whose hour of resurrection has not yet arrived. For thus the Scripture speaks of the dead as sleeping, because it wishes them to be regarded as destined to awake, that is, to rise again.
But He, wounded and asleep in the tomb, awoke on the third day, and became “like a sparrow that sits alone on the housetop,” that is, on the right hand of His Father in Heaven: and now “dies no more, death shall no more have dominion over Him.” Hence He differs widely from those whom God has not yet remembered to cause their resurrection after this manner: for what was to go before in the Head, was kept for the Body in the end. God is then said to remember, when He does an act: then to forget, when He does it not: for neither can God forget, as He never changes, nor remember, as He can never forget.
“I am counted” then, by those who know not what they do, “as a man that has no help:” while I am “free among the dead,” I am held by these men “like them that are wounded, and lie in the grave.” Yet those very men, who account thus of Me, are further said to be “cut away from Your hand,” that is, when I was made so by them, “they were cut away from Your hand;” they who believed Me destitute of help, are deprived of the help of Your hand: for they, as he says in another Psalm, have dug a pit before me, and are fallen into the midst of it themselves.
I prefer this interpretation to that which refers the words, “they are cut away from Your hand,” to those who sleep in the tomb, whom God has not yet remembered: since the righteous are among the latter, of whom, even though God has not yet called them to the resurrection, it is said, that their “souls are in the hands of God,” that is, that “they dwell under the defence of the Most High; and shall abide under the shadow of the God of Heaven.” But it is those who are cut away from the hand of God, who believed that Christ was cut off from His hand, and thus accounting Him among the wicked, dared to slay Him.
Source: The Enarrations, or Expositions, on the Psalms (New Advent)