Where do the dead wait before the resurrection? Do Christians go to heaven at death?

Justin Martyr c. 100–c. 165 ADDialogue with Trypho 80.4

If you meet some who are called Christians but do not confess this, but dare to blaspheme the God of Abraham, Isaac and Jacob, who say there is no resurrection of the dead, but that their souls are taken up into heaven at the moment of death, do not suppose they are Christians.

Justin is attacking Gnostics who replaced the resurrection with the soul's flight to heaven, not every hope of being with Christ.

Irenaeus of Lyons c. 130–c. 202 ADAgainst Heresies 5.31.2

The souls go to the place appointed for them by God, and there they dwell until the resurrection, waiting for the resurrection; then, receiving their bodies back and rising whole, that is, bodily, just as the Lord also rose, they shall in this way come into the sight of God.

Irenaeus is opposing Gnostics who sent the saved soul straight up at death. Just before, he argues the Lord himself went to the place of the dead and rose bodily first; his disciples follow the same order. The passage survives in this Greek fragment and in the old Latin translation.

Tertullian c. 155–c. 220 ADOn the Soul 55.4–5

"But no," you say, "in paradise, to which the patriarchs and prophets have already moved from the underworld, as an appendage of the Lord's resurrection." Then how is it that the region of paradise, shown to John in the Spirit beneath the altar, shows no other souls in it but the martyrs? How did Perpetua, bravest martyr, on the day of her passion see only her fellow martyrs there, in her vision of paradise, unless the sword that guards paradise gives way to none but those who have died in Christ, not in Adam? ... Your own blood is the whole key to paradise.

For Tertullian, souls wait in the underworld until the resurrection; only martyrs go at once to paradise.

Cyprian of Carthage c. 200–258 ADOn Mortality 26

Let us welcome the day which assigns each of us to his own home, which snatches us from here, frees us from the snares of the world, and restores us to paradise and the kingdom. ... We count paradise as our homeland. ... A great number of our dear ones awaits us there: parents, brothers, children, a large and crowded throng longs for us, already sure of their own safety, still anxious for ours.

Written during the plague of 252 to comfort Christians who feared dying in bed rather than as martyrs.

Pope Benedict XIIBenedictus Deus Denzinger no. 530

Immediately after their death, and after the purification already mentioned in those who needed such purification, even before they take up their bodies again and before the general judgment ... they were, are and will be in heaven, in the kingdom of heaven and in the heavenly paradise, with Christ, gathered into the company of the holy angels ... they saw and see the divine essence by a vision that is intuitive and also face to face, no creature coming between in the role of the object seen, but the divine essence showing itself to them directly, nakedly, clearly and openly ... the souls of those who have already died are truly blessed, and have life and eternal rest.

The bull settled the dispute stirred by Pope John XXII, who had preached that the dead wait until the judgment to see God. Benedict defines the opposite for the purified: the sight of God at once, before the resurrection, while the body is still awaited. The scan of Denzinger is poorly OCRd, so the Latin follows the standard printed text.

Martin Luther 1483–1546 ADLectures on Genesis on Genesis 25:8 (Weimar Ausgabe 43)

This, then, is the first place in all holy Scripture which testifies that the death of the saints is calm and precious in the sight of God: they do not taste death, but fall asleep most sweetly. ... The resting-places of souls are the word of God, that is, his promises, in which we fall asleep. ... we depart safe and quiet into the bosom of Christ.

Luther on the death of Abraham, in the Genesis lectures printed in the Weimar Ausgabe: his fullest statement of the sleep of the dead. The search gap named his 1532 sermons, which are in German; this is the matching statement in the same Weimar edition, in Latin. The sleep is a rest held in God's word and promise until the resurrection.