“qad aflaha”—and He did not say “qad aflahat.”
They are answered as follows:
To begin with, this is a departure from idiomatic Arabic; it is only acceptable when some part of the context makes the feminine clear, as in His words,
{And whoever of you devoutly obeys Allah and His Messenger and acts righteously} (Al-Ahzab 31),
for the phrase “of you” (min-kunna) ⦗1⦘ shows that women are intended, hence the verb appears in the feminine form. The same applies to His statement,
{And among them is he who listens to you} (Yunus 42),
and other similar examples. Here, however, neither the word man (“who”) nor anything that follows it indicates that the feminine soul is meant: He did not say “qad aflahat,” nor did He say, “Successful indeed is one of the souls that He purifies.” What immediately precedes is His saying,
{By the soul and the One who proportioned it, and inspired it with its debauchery and its God-consciousness} (Ash-Shams 7–8),
then He says,
{Successful indeed is he who purifies it, and ruined indeed is he who debases it}.
Thus, an antecedent already exists to which the feminine pronoun can legitimately return, and no evidence has been offered that it should refer to anything else ⦗2⦘.
Therefore, it is impermissible to read into the verse a meaning for which there is no textual support; such sophistry ⦗3⦘ is something from which the speech of Allah, mighty and exalted, must be kept free.