I struggled with this passage this past week, so I'm sorry if this seems disjointed or incomplete. It just seemed so circular (much like Tammi said on Friday!). My husband has explained much of the Bible appears cyclical because of the difference in styles of teaching and story telling. I'm sure that is what is in play here.
In verse 10, John tells us God's testimony is greater. God's testimony came in several forms - one of the most known happening in Matthew 5:16-17 when John the Baptist baptized Jesus and a dove and a voice came from Heaven proclaiming Jesus to be the Son of God. Also today, we have the Bible as a whole - a Holy Spirit inspired transcript of God speaking to humans of His love, grace, and mercy.
If we believe in Jesus Christ, we accept God's Word. If we do not believe God's Word, we are calling God a liar.
Verse 11 is my favorite though. It's like a movie tagline: "And this is the testimony: God has given us eternal life, and this life is in his Son." All of the Bible is there. God's love and gracious gift, the birth of Jesus, Jesus's sacrifice, and our gain.
When we accept Jesus, we accept life, forever.
Isn't that a wonderful comfort? To know that God has given us eternal life through His Son. And all we have to do is accept it.