Thank you for contacting BibleAsk.
The verse in Mark 12:26, 27 reads like this: “And as touching the dead, that they rise; have ye not read in the book of Moses, how in the bush God spake unto him, saying, I am the God of Abraham, and the God of Isaac, and the God of Jacob? He is not the God of the dead, but the God of the living: ye therefore do greatly err.”
Jesus was speaking about the resurrection when He spoke about God being the God of the living. He gave no indication at all that Abraham, Isaac and Jacob were living now. God is the God of the living, in the same sense that He has power over the grave and over death.
All rewards and punishments will be given at the resurrection not at death. In John 5:28, 29 Jesus said, “Marvel not at this: for the hour is coming, in the which all that are in the graves shall hear his voice, And shall come forth; they that have done good, unto the resurrection of life; and they that have done evil, unto the resurrection of damnation.” Here, Jesus made it very clear that the righteous would be rewarded with immortality at the time of the resurrection, and the wicked would be punished for their sins at the time of their resurrection.
Obviously, no one can be punished or rewarded until after the judgment takes place. Even an earthly judge would be considered very wicked to send a man to his punishment before having his trial and hearing the judgment. In 2 Peter 2:9 we read: “The Lord knoweth how to deliver the godly out of temptations, and to reserve the unjust unto the day of judgment to be punished.” The Bible emphatically states that no one will be punished until after the judgment takes place at the end of the world.
There are scores of other texts which prove that the dead do not go immediately to their punishment or reward. They are all sleeping the sleep of death in their graves until the glorious resurrection morning when all will come forth to receive the judgment and the rewards. For more on the state of the dead please check the following link: https://bibleask.org/bible-answers/112-the-intermediate-state/
In His service,