The idea of a general resurrection (and heaven) was well expressed in very early Jewish belief.
• Taught in Job 14.
• Taught in Psalms.
• Taught in Hosea 13 etc.
This is relevant because it entails that the Old Testament teaches a general resurrection.
• Daniel 12:2-3 — Many of those who sleep in the dust of the ground will awake, these to everlasting life, but the others to disgrace and everlasting contempt. 3 Those who have insight will shine brightly like the brightness of the expanse of heaven, and those who lead the many to righteousness, like the stars forever and ever.
• Isaiah 25:8 — He will swallow up death for all time, And the Lord God will wipe tears away from all faces, And He will remove the reproach of His people from all the earth; For the Lord has spoken.
• Isaiah 26:19 — Your dead will live; Their corpses will rise. You who lie in the dust, awake and shout for joy, For your dew is as the dew of the dawn, And the earth will give birth to the departed spirits.
In the book of Genesis, it is implied that Adam (and those after him) faced ultimate/permanent death if and only if they transgressed one or more of God's commandments (i.e. sinned).
• In Genesis, we read of Adam and Eve initially being created by God in a paradise—“the garden of Eden.” They were given an opportunity to sin, in disobeying God’s command to “not eat” of a particular fruit tree (for in doing so, they would intimately know sin/guilt), and Gen 2:17 — “in the day [Heb. “Yom”; i.e. time-period] that you eat from it you will surely die.”
This is relevant because the Old Testament implies a new age will come when all who have freely aimed to submit to God’s will (via obedience, animal sacrifices etc.) will be cleansed of their sin, and will consequently not be held by death any longer.
• The Old Testament says the Messiah will live on.
• Isaac’s father anticipated his son’s death and resurrection.
• Psalm 16:10 says (“[won’t] allow your Holy one to undergo decay).
• Hosea 6:1-2
• Job 19:25-26
The Old testament teaches that God is all-powerful and all-good.
• It teaches God has the power and will to preserve the righteous (who he loves)
This is relevant because belief in a heaven—whence all evil is destroyed—is a fairly straightforward inference from these two properties, and a resurrection of the righteous dead is nearby this inference, and a natural hope for those who believe in such a God. (Note: this line of inference is amplified by the fact that, indisputable, later Jews did all accept these things and the Bible did directly teach it.)