Other versions say *freely by His grace*.
In the Greek, the word freely* is this.
http://biblehub.com/greek/1432.htm
dórean: as a gift, to no purpose
Original Word: δωρεάν
Part of Speech: Adverb
Transliteration: dórean
Phonetic Spelling: (do-reh-an')
Short Definition: as a free gift, without payment, freely
Definition: as a free gift, without payment, freely.
HELPS Word-studies
Cognate: 1432 dōreán(the adverbial form of 1431/dōrea) – something freely done (as gratis), i.e. without "cause"; unearned (undeserved); freely given (without cost) hence not done out of mere obligation or compulsion. See 1431 (dōrea).
FREELY given.
Not attained by going to confession and doing penance to earn it or become worthy of it>
FREELY forgiven by God's grace.
Without strings.
The Catholic requirements to attain forgiveness make it a work and hence wages due.
If you do *X* then God does *Y*. By our doing it, it makes God beholden to us for what we did and then He is obligated to *forgive* us.
But that's not forgiveness.
Forgiveness by it's very nature is not earned or deserved. If it was, once again, it's wages due for works performed.
It ceases to be forgiveness but an obligation.
God only forgives those who repent of their sins. II Cor. 7:10 says, “[G]odly grief produces a repentance that leads to salvation.” I John 1:9 says, “If we confess our sins, he . . . will forgive our sins.”
God had sent Jesus to forgive sins, but after his resurrection Jesus told the apostles, “‘As the Father has sent me, even so I send you.’ And when he had said this, he breathed on them, and said to them, ‘Receive the Holy Spirit. If you forgive the sins of any, they are forgiven; if you retain the sins of any, they are retained’” (John 20:21–23).
(This is one of only two times we are told that God breathed on man, the other being in Genesis 2:7, when he made man a living soul. It emphasizes how important the establishment of the sacrament of penance was.)
Note that the power Christ gave the apostles was twofold: to forgive sins or to hold them bound, which means to retain them unforgiven. Several things follow from this. First, the apostles could not know what sins to forgive and what not to forgive unless they were first told the sins by the sinner. This implies confession. Second, their authority was not merely to proclaim that God had already forgiven sins or that he would forgive sins if there were proper repentance.
Such interpretations don’t account for the distinction between forgiving and retaining—nor do they account for the importance given to the utterance in John 20:21–23. If God has already forgiven all of a man’s sins, or will forgive them all (past and future) upon a single act of repentance, then it makes little sense to tell the apostles they have been given the power to “retain” sins, since forgiveness would be all-or-nothing and nothing could be “retained.”
Furthermore, if at conversion we were forgiven all sins, past, present, and future, it would make no sense for Christ to require us to pray, “And forgive us our debts, as we also have forgiven our debtors,” which he explained is required because “if you forgive men their trespasses, your heavenly Father also will forgive you; but if you do not forgive men their trespasses, neither will your Father forgive your trespasses” (Matt. 6:12–15).
Is the Catholic who confesses his sins to a priest any better off than the non-Catholic who confesses directly to God? Yes. First, he seeks forgiveness the way Christ intended. Second, by confessing to a priest, the Catholic learns a lesson in humility, which is avoided when one confesses only through private prayer. Third, the Catholic receives sacramental graces the non-Catholic doesn’t get; through the sacrament of penance sins are forgiven and graces are obtained. Fourth, the Catholic is assured that his sins are forgiven; he does not have to rely on a subjective “feeling.” Lastly, the Catholic can also obtain sound advice on avoiding sin in the future.