Here is a bit from 2 Corinthians 5, which is this Sunday’s scripture.
Now we know that if the earthly tent we live in is destroyed, we have a building from God, an eternal house in heaven, not built by human hands. . . . Therefore we are always confident and know that as long as we are at home in the body we are away from the Lord. We live by faith, not by sight. We are confident, I say, and would prefer to be away from the body and at home with the Lord. So we make it our goal to please him, whether we are at home in the body or away from it. For we must all appear before the judgment seat of Christ, that each one may receive what is due him for the things done while in the body, whether good or bad.
An eternal house in heaven. It sort of reminds me of Psalm 23:6, “Surely goodness and love will follow me all the days of my life, and I will dwell in the house of the LORD forever.”
A generation or two later Mark and Matthew wrote about the Kingdom of God. Here is sort of a run on of quotes. First from Mark:
“The time has come,” he said. “The kingdom of God is near. Repent and believe the good news!” 1:15; He told them, “The secret of the kingdom of God has been given to you. But to those on the outside everything is said in parables.” 4:11; He also said, “This is what the kingdom of God is like. A man scatters seed on the ground . . . 4:26; 4:30 (like a mustard seed); And he said to them, “I tell you the truth, some who are standing here will not taste death before they see the kingdom of God come with power.” 9:1.
“But if I drive out demons by the Spirit of God, then the kingdom of God has come upon you.” 12:28; “Again I tell you, it is easier for a camel to go through the eye of a needle than for a rich man to enter the kingdom of God.” 19:24; Jesus said to them, “I tell you the truth, the tax collectors and the prostitutes are entering the kingdom of God ahead of you. For John came to you to show you the way of righteousness, and you did not believe him, but the tax collectors and the prostitutes did. And even after you saw this, you did not repent and believe him.” 21:32; “Therefore I tell you that the kingdom of God will be taken away from you and given to a people who will produce its fruit.” 21:43;
There is some mention of entering the Kingdom of Heaven for sure. And, without quoting them I think there are ample passages suggesting that Jesus and his followers believed in an afterlife. But, does it sound like the Kingdom of God is describing Heaven or the afterlife?