How do we know Adam is in heaven?
Eastern Christian tradition says so:
Kontakion Tone 1:
As God, Thou didst rise from the tomb in glory, raising the world with Thyself,
Human nature praises Thee as God, for death has vanished!
Adam exults, O Master! Eve rejoices, for she is freed from bondage, and cries to Thee:
Thou art the Giver of Resurrection to all, O Christ!
Troparion Tone 2:
Hell became afraid, O almighty Savior,
seeing the miracle of Thy Resurrection from the tomb! The dead arose!
Creation with Adam, beheld this and rejoiced with Thee! And the world,
O my Savior, praises Thee forever.
Kontakion Tone 3:
On this day Thou didst rise from the tomb, O Merciful One,
leading us from the gates of death.
On this day Adam exults as Eve rejoices;
with the prophets and patriarchs they unceasingly praise the divine majesty of Thy power!
Troparion Tone 5:
Thou didst descend into hell, O my Savior,
shattering its gates as Almighty;
resurrecting the dead as Creator, and destroying the sting of death.
Thou hast delivered Adam from the curse, O Lover of Man,
and we all cry to Thee: O Lord, save us!
Kontakion Tone 8:
By rising from the tomb,
Thou didst raise the dead and resurrect Adam.
Eve exults in Thy Resurrection, and the world celebrates Thy Rising from the dead,
O greatly Merciful One!