You say that as if you know it; do you, and how do you know it?
Probably this way...
1 John 3:23-24
23. And this is his command: to believe in the name of his Son, Jesus Christ, and to love one another as he commanded us.
24. Those who obey his commands live in him, and he in them. And this is how we know that he lives in us: We know it by the Spirit he gave us.
1 John 5:3-5
3. This is love for God: to obey his commands. And his commands are not burdensome,
4. for everyone born of God overcomes the world. This is the victory that has overcome the world, even our faith.
5. Who is it that overcomes the world? Only he who believes that Jesus is the Son of God.
1 John 5:13
I write these things to you who believe in the name of the Son of God
so that you may know that you have eternal life.