First off, we know that we are not ‘just dead’. Consider the following:
CCC#1021
Death puts an end to human life as the time open to either accepting or rejecting the divine grace manifested in Christ. [Cf. 2 Tim 1:9-10] The New Testament speaks of judgement primarily in its aspect of the final encounter with Christ in his second coming, but also repeatedly affirms that each will be rewarded immediately after death in accordance with his works and faith. The parable of the poor man Lazarus and the words of Christ on the cross to the good theif, as well as other New Testament texts speak of a final destiny of the souls—a destiny which can be different for some and for others. [Cf. Lk 16:22; 23:43; Mt 16:26; 2 Cor 5:8; Phil 1:23; Heb 9:27; 12:23.]
#1022
Each man receives his eternal retribution in his immortal soul at the very moment of his death, in a particular judgement that refers his life to Christ: either entrance into the blessedness of heaven—through a purification [Cf. Council of Lyons II (1274): DS 857-858; Council of Florence (1439): DS 1304-1306; Council of Trent (1563): DS 1820.] or immediately, [Cf. Benedict XII,* Benedictus Deus (1336): DS 1000-1001; John XXII, Ne super his (1334): DS 990.]—or immediate and everlasting damnation. [Cf. Benedict XII, *Bendictus Deus (1336): DS 1002.]
At the evening of life, we shall be judged on our love. [St. John of the Cross, *Diochos 64.]
We also know that Jesus did open the Gates of Heaven, and that all went to Sheol (though some to Paradise, or Abraham’s Bosom) prior to Christ’s descent into Hades (Sheol). (With the exception of a few great saints like Elijah). Take a look at the section in the Catechism on this:
usccb.org/catechism/text/pt1sect2chpt2art5.htm#p1. The OT saints were waiting for Christ to open the gates to Heaven. (Scriptural support is cited by the Catechism for this teaching).
Of specific significance (though I encourage to look at the whole section) is:
CCC#633:
Scripture calls the abode of the dead, to which the dead Christ went down, “hell”—*Sheol * in Hebrew or
Hades in Greek—because those who are there are deprived of the vision of God. [Cf. Phil 2:10; Acts 2:24; Rev 1:18; Eph 4:9; Pss 6:6; 88:11-13.] Such is the case for all the dead, whether evil or righteous, while they await the redeemer: which does not mean that their lot is identical, as Jesus shows through the parable of the poor man Lazarus who was received into “Abraham’s bosom”: [Cf. Ps 89:49; 1 Sam 28:19; Ezek 32:17-32; Lk 16:22-26.] “It is precisely these holy souls, who awaited their Saviour in Abraham’s bosom, whom Christ the Lord delivered when he descended into hell.”
Roman Catechism I, 6, 3.] Jesus did not descend into hell to deliver the damned, nor to destroy the hell of damnation, but to free the just who had gone before him. [Cf. Council of Rome (745): DS 587; Benedict XII, *Cum dudum (1341): DS 1011; Clement VI,
Super quibusdam (1351): DS 1077; Council of Toledo IV (625): DS 485; Mt 27:52-53.]
#634
"The gospel was preached even to the dead. [1 Pet 4:6.] The descent into hell brings the Gospel message of salvation to complete fulfillment. This is the last phase of Jesus’ messianic mission, a phase which is condensed in time but vast in its real significance: the spread of Christ’s redemptive work to all men of all times and all places, for all who are saved have been made sharers in the redemption.
(continued)