The Catechism of the Summa - Tertia Pars - XLV. OF HEAVEN (A)

(A)

What is heaven?

It is that place where the holy angels have lived since the beginning of the world and to which are admitted all the just who have been redeemed by the Blood of Jesus Christ since the day of His glorious Ascension.

What is necessary for the just to be admitted into heaven?

They must have reached the term of their mortal life, and must have no debt to pay to the justice of God (LXIX. 2).

Are any souls of the just admitted into heaven immediately after their death?

Yes; they are those souls who have received in their full effect the application of the merits of Jesus Christ; or who, whilst on earth, in union with the satisfaction of Jesus Christ have offered to God full satisfaction due to their sins (ibid.).

Children that die after having received baptism and before they have come to the age when they would be capable of sinning, are they admitted immediately to heaven?

Yes, because original sin, which for them was the only obstacle, has been washed away by baptism.

Is the case the same as regards those adults who, although they have committed mortal sins, receive baptism in good dispositions and die immediately afterwards or before they commit sin again?

Yes, because the sacrament of Baptism applies in all their fulness the merits of the Passion of Jesus Christ (Third Part, LXIX. 1, 2, 7, 8).

And those who having committed sins, even mortal, since their baptism, and who have not made complete satisfaction for them, but who nevertheless at the moment of dying offer their life to God by a perfect act of charity, are they received into heaven immediately after their death?

Yes; especially when this perfect act of charity is martyrdom (Second Part: Second Section, CXXIV. 3).

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