Now this is eternal life: that they know you, the only true God, and Jesus Christ, whom you have sent.John 17:3 NIV
I think it is common for us to equate eternal life with the duration of that life. But here, Jesus defined eternal life in terms other than duration. He described it regarding its quality. Eternal life is knowing God the Father and the Lord Jesus Christ.
Knowing God is much more than just intellectual knowledge. It refers to relational knowledge. Eternal life is primarily about being in a personal relationship with the triune God. And this relationship is one that Jesus goes on to describe as being intimate. His prayer for us is that we might be one with each other. And that we might be in the Father and the Son. Eternal life will indeed last forever. But more than anything, it is a loving relationship with our creator and savior. A relationship that God’s people experience even now.