1 John 5:19-20

We know [for a fact] that we are of God, and the whole world [around us] lies in the power of the evil one [opposing God and His precepts]. And we [have seen and] know [by personal experience] that the Son of God has [actually] come [to this world], and has given us understanding and insight so that we may [progressively and personally] know Him who is true; and we are in Him who is true—in His Son Jesus Christ. This is the true God and eternal life.