He is not the God of the dead, but of the living, for to him all are alive.
Here the Teacher affirms the coming resurrection of the dead. And He reveals that while the dead are temporarily separated from their bodies, they are in some sense still very much alive!
Jesus quotes Moses who referred to God as the God of Abraham, Isaac and Jacob. Yet at the time, all these men were dead. How then could God still be their God?
The obvious answer? They still live. At death their spirits returned to God and wait with all others who have died for the day of the resurrection from the dead.
Everyone who ever lived still lives!
But those who are considered worthy of taking part in that age and in the resurrection from the dead will neither marry nor be given in marriage, and they can no longer die; for they are like the angels. They are God's children, since they are children of the resurrection.
Some of the teachers of the law responded, "Well said, teacher!" And no one dared to ask him any more questions.