Eternity refers to time, time with no end. God is the only being Who has no beginning and no end, so He is the epitome of eternity.
People (not the Bride of Christ) who are resurrected in the Kingdom will have an opportunity to live forever. The very reason Jesus came to earth and became our ransom was to offer us eternal life. “For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life”, John 3:16 (NKJV).
Remember when Adam and Eve sinned, and God barred the first couple’s access to the Tree of Life? Their human lives depended upon eating the fruit from the Tree of Life. Genesis 3:22 (CSB), “The LORD God said, ‘…he (Adam) must not reach out, take from the tree of life, eat, and live forever."
Human eternal life will also be sustained by the Tree of Life in God’s kingdom. Revelation 22:14 (RSV), “Blessed are those who wash their robes, that they may have the right to the tree of life and that they may enter the city (New Jerusalem) by the gates.”
When a person is first resurrected, he will have all his experiences and memories as tools to begin to learn how to obey the Lord’s divine law. He will be taught how to live righteously as Habakkuk 2:14 says, “For the earth will be full of the knowledge of the Lord as the waters cover the sea.”
With knowledge and experience, each person can then avail himself, if he so desires, of the promise given in Romans 6:23, “For the wages of sin is death, but the gift of God is eternal life through Jesus Christ our Lord.”