In Jesus story of Lazarus and the rich man (Luke 16:19-31) He certainly taught that there was consciousness after death. Lazarus was comforted, while the rich man was tormented. In Matthew 22:23-33 when Jesus taught the Sadducees about the resurrection, He quoted Exodus 3:6, “I am the God of Abraham, the God of Isaac, and the God of Jacob.” Jesus then said, “God is not the God of the dead, but of the living.” Jesus clearly taught that the dead were living and conscious. Remember that in Luke 9:28-36 Moses and Elijah appeared with Jesus when he was transfigured and even spoke with Him concerning His upcoming death. Moses and Elijah were certainly conscious though they had been dead for up to 1500 years. In II Samuel 12:23 when David’s first child by Bathsheba had died, David, in expressing his hope of seeing the child again said, “I shall go to him, but he shall not return to me.”
On the other hand, Ecclesiastes 9:4-6 seems to indicate that there is no knowledge of what is going on in this life after one is dead. In I Samuel 28:14-15, when Saul used a witch to call up Samuel from the dead, Samuel seemed angry saying, “Why have you disturbed me by bringing me up?” Samuel indicates that he was not aware of Saul’s recent troubles and chastises him for calling him up when the Lord had departed from him.