Here are many Bible verses about eternity.

Truly, truly, I say to you, whoever hears my word and believes him who sent me has eternal life. He does not come into judgment, but has passed from death to life.- John 5:24

For the wages of sin is death, but the free gift of God is eternal life in Christ Jesus our Lord.- Romans 6:23

He has made everything beautiful in its time. Also, he has put eternity into man’s heart, yet so that he cannot find out what God has done from the beginning to the end.- Ecclesiastes 3:11

And this is eternal life, that they know you the only true God, and Jesus Christ whom you have sent.- John 17:3

Before the mountains were brought forth, or ever you had formed the earth and the world, from everlasting to everlasting you are God.- Psalm 90:2

For God so loved the world, that he gave his only Son, that whoever believes in him should not perish but have eternal life.- John 3:16

For thus says the One who is high and lifted up, who inhabits eternity, whose name is Holy: “I dwell in the high and holy place, and also with him who is of a contrite and lowly spirit, to revive the spirit of the lowly, and to revive the heart of the contrite.- Isaiah 57:15

For the one who sows to his own flesh will from the flesh reap corruption, but the one who sows to the Spirit will from the Spirit reap eternal life.- Galatians 6:8

But the Lord is the true God; he is the living God and the everlasting King. At his wrath the earth quakes, and the nations cannot endure his indignation.- Jeremiah 10:10

You make known to me the path of life; in your presence there is fullness of joy; at your right hand are pleasures forevermore.- Psalm 16:11

The grass withers, the flower fades, but the word of our God will stand forever.- Isaiah 40:8