Blasphemy against the Holy Spirit means final impenitence. This means that someone who refuses to repent and believe in God, through death, cannot be forgiven and thus cannot be saved. Someone who does not choose God even in their final moments, does not want Him. Therefore, because every human being has free will, the Lord will not force someone to be with Him for all eternity who does not want Him.
One may object that surely if God saves someone who is impenitent through death, that that person will repent and choose God. But God would then not be a Merciful Savior, but a tyrant, for He would not be just. The Lord respects our decision to choose or reject Him. This freedom may seem cruel, but as we discussed earlier, without this freedom, we would be robots, forced to choose God. We could not then love God, because love is a free act of the will. Without freedom, there cannot be true love. As Ven. Fulton Sheen put it: “the greatest freedom that there is in this world is the freedom to be a saint” (Freedom 22:48-22:54). But without free will, there would be no such option, and thus there would be no Heaven, but only Hell, for those who cannot love cannot participate in the Divine Love of God.
This impenitence includes the innermost depths of the soul, meaning that for someone to blaspheme against the Holy Spirit, he must, even in his heart of hearts, refuse God through his final moments. That means that someone who chooses God, even in the final moments of their lives, has the possibility of salvation. Once, when counseling a woman grieving her husband who committed suicide, St. John Vianney had a vision where the Lord revealed to the priest that the woman’s husband was saved because he repented on the way down the bridge he jumped off. God indeed gives us every opportunity to be saved.
Now, it can be easy for one to say: “surely, at death, I will repent. It matters not how I live now.” But this thinking is pitiable and erroneous, for no one knows when or how his death will come. Perhaps he may be hit by a bus and die instantly, without the chance to repent. Perhaps part of a building under construction will fall off and hit him, killing him instantly. We may think that such an occurrence is unlikely, and we are probably right. But it is unlikely until it happens, and once it happens, what is done is done, and there is no more time left for us to choose God.
But we should not return to God for fear of Hell, though that is still a sufficient motive for attaining salvation. Our primary motive for repenting of our sins and returning to God must be our love for God, and thus our sorrow for having offended Him for His sake. We can contemplate His love on the cross and behold His mercy worked in our lives when He has been patient with us time and time again, when we turned our backs on Him. Indeed, many souls, fearing Hell, but also having a deep sense of remorse for their sins in life, repent on their deathbeds. They realized by experience, and not only by thought, that “all is vanity” besides God (Eccl 1:14).
Let us do now, then, what we would wish to do on our deathbeds, were God to give us that great grace of being able to repent to Him. “Behold, now is the acceptable time; behold, now is the day of salvation” (2 Cor 6:2).