And [in addition], we know that the Son of God has come [in a physical body, See 4:2] and has given us understanding, so that we can know the True One [i.e., God], and that we are in [fellowship with] the True One, even His Son Jesus Christ. This Son is the true God and eternal life.

The person who [sincerely] believes in God's Son has the evidence [of it] within his heart, [confirming God's testimony]. The person who does not believe God [i.e., what He says about Jesus], accuses Him of lying, because he has not accepted the [irrefutable] testimony of God concerning [the identity and mission of] His Son.

Whoever proclaims that Jesus is the Son of God, God [continually] lives in that person's heart, and he lives in [fellowship with] God [See 2:23].

The person who has the Son [in his heart] possesses this "life;" the one who does not have the Son of God does not possess this "life."

But, if we live in the light [of righteousness] just like God [constantly] lives in the light [of righteousness], we can truly share a relationship with one another and [can know that] the blood of Jesus, God's Son, continues to cleanse [our spirits] from all of our sins.

If we [are willing to] accept the testimony of people about matters, [surely we ought to accept that] the testimony of God is more reliable; because the testimony of God is that He has presented [confirming] testimony concerning [the identity and mission of] His Son.

We know that every person who has been [spiritually] conceived [by God and eventually born] does not continue in [a life of] sin, but God's one and only conceived [Son] keeps him [from continuing to sin], and the evil one [i.e., Satan] does not continue to touch him [i.e., continue to control his life].