The Lord said, “I tell you, every sin and blasphemy will be forgiven men, but the blasphemy against the Spirit will not be forgiven. Anyone who speaks a word against the Son of Man will be forgiven, but anyone who speaks against the Holy Spirit will not be forgiven, either in this age or in the age to come” (Mt. 12:31-32; cf. also Mk. 3:28-30 and Lk. 12:10).
What is this “unforgivable sin” or “unpardonable sin” or “blasphemy against the Holy Spirit”? How does such sin relate to my life? Could I have possibly committed such sin for which I will be never forgiven?
If you have any fears and concerns that perhaps, unbeknown to you, you have committed the unpardonable sin, most likely you have not committed it! Those who have committed such sin would have no regrets and scruples about it! They would have no interest in the forgiveness of God.
Early on, the Church had a strict interpretation of the sin against the Holy Spirit. We see this in the Acts of the Apostles, when Ananias and his wife dropped dead because they had lied to the Holy Spirit (Acts 5). The Church understood the sin of apostasy, committed after one had joined the Church of the believers, as an unpardonable sin. The letter to the Hebrews refers twice to such a sin:
For it is impossible to restore again to repentance [to re-admit them to the Church as penitents] those who have once been enlightened [baptized], and have tasted the heavenly gift [received Holy Communion], and have shared in the Holy Spirit [displaying the special gifts of the Holy Spirit], and have tasted the goodness of the word of God [being exposed to the Holy Scriptures, which were reserved only for the believers] and the powers of the age to come, and then have fallen away, since on their own they are crucifying again the Son of God and are holding him up to contempt. (Heb. 6:4-6)
And again, “For if we willfully persist in sin after having received the knowledge of the truth, there no longer remains a sacrifice for sins, but a fearful prospect of judgment, and a fury of fire that will consume the adversaries” (Heb. 12:26-27).
The letter to the Hebrews is not the only one which takes such a strict view. St. Peter holds the same view,
For if, after they [the false teachers] have escaped the defilements of the world through the knowledge of our Lord and Savior Jesus Christ, they are again entangled in them and overpowered, the last state has become worse for them than the first. For it would have been better for them never to have known the way of righteousness than, after knowing it, to turn back from the holy commandment that was passed on to them. It has happened to them according to the true proverb, ‘The dog turns back to its own vomit’ [Prov. 26:11] and ‘The sow is washed only to wallow in the mud’ (2 Pet. 2:20-22).
St. Jude too refers to those who had gained entry into the Church (Jude 6), though “secretly,” “people devoid of the Spirit” (v. 19), “for whom the nether gloom of darkness has been reserved for ever” (v. 13): they have been already condemned because of their destructive teachings.
Today, the Church understands as “unpardonable” only the sin for which people do not ask God to forgive them, that is, when people reject stubbornly Jesus Christ and His gift of eternal life to the end of their lives. Therefore, only the unrepentant sin is unforgivable. Anyone who sincerely repents of his sins and asks for God’s forgiveness will receive it. No human offence is beyond divine forgiveness. The Church forgives any sin committed, as the Lord commanded us to forgive, even unto “seventy times seven” (Mt. 18:22), that is always. Occasionally for very grave sins the Church may cut someone off from Holy Communion, that is, from Christ our life. This is a temporary measure done in order for us to realize the severity of our sin and to come to complete repentance. We should view such action as therapeutic in nature. It is to be compared to a very sick person who needs to eat very light foods and avoid meat and solid foods, which would harm him.
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