Youcat commented through CCC – Question n. 162.

YOUCAT Question n. 162 - But if God is love, how can there be a hell?

(Youcat answer) God does not damn men. Man himself is the one who refuses God’s merciful love and voluntarily deprives himself of (eternal) life by excluding himself from communion with God.              

A deepening through CCC

(CCC 1033) We cannot be united with God unless we freely choose to love him. But we cannot love God if we sin gravely against him, against our neighbor or against ourselves: "He who does not love remains in death. Anyone who hates his brother is a murderer, and you know that no murderer has eternal life abiding in him" (1 Jn 3:14-15). Our Lord warns us that we shall be separated from him if we fail to meet the serious needs of the poor and the little ones who are his brethren (Cf. Mt 25:31-46). To die in mortal sin without repenting and accepting God's merciful love means remaining separated from him for ever by our own free choice. This state of definitive self-exclusion from communion with God and the blessed is called "hell."       

Reflecting and meditating 

(Youcat comment) God yearns for communion even with the worst sinner; he wants everyone to convert and be saved. Yet God created man to be free and respects his decisions. Even God cannot compel love. As a lover he is “powerless” when someone chooses hell instead of heaven.          

(CCC Comment)

(CCC 1861) Mortal sin is a radical possibility of human freedom, as is love itself. It results in the loss of charity and the privation of sanctifying grace, that is, of the state of grace. If it is not redeemed by repentance and God's forgiveness, it causes exclusion from Christ's kingdom and the eternal death of hell, for our freedom has the power to make choices for ever, with no turning back. However, although we can judge that an act is in itself a grave offense, we must entrust judgment of persons to the justice and mercy of God.             

(The next question is: What is the Last Judgment?)