According to the Bible itself, Adam was both punished and forgiven. He was never cursed, nor did he remain sinful forever.

This is clear from the text

 Adam was punished
After the sin, God pronounces consequences: toil, pain, and death (Genesis 3:16–19).

 Adam was not cursed personally

The Bible says the ground was cursed because of Adam, not Adam himself:

 “Cursed is the ground because of you.” (Genesis 3:17)

And not just Adam, but also his children were never called cursed in the Bible.

 So, biblically: Adam, though sinful, was punished but never called cursed. Jesus, though sinless, was not only said to ‘become a curse’ but also punished, crucified, tortured, and killed. Is this just?!

 Adam was shown mercy and care
“And the LORD God made for Adam and for his wife garments of skins and clothed them.” (Genesis 3:21)

This indicates continued divine care, not abandonment.

 Adam continued in relationship with God
Adam speaks, names, and lives by God’s command afterward (Genesis 4:1–2), this implies that Adam was forgiven.

 Nowhere does the Bible state that Adam remained unforgiven or eternally fallen.

The idea of inherited guilt and permanent fall develops later in Christian theology, especially in Paul’s writings (e.g., Romans 5).

So even biblically:  Sin → punishment → mercy, not eternal condemnation.