To know the truth means that the word must become flesh; that’s what truth is. That is how Jesus could describe Himself as truth. There is a false truth; the word that does not become flesh; it is always learning and never coming to the knowledge of the truth. False truth is the currency of religion.
Life is to know God the Father and Jesus whom He sent; “this is eternal life, that they should know you, the only true God and the one you sent Jesus Christ” (John 17:3). The verb “know” is in the subjunctive. It is also epignosko, meaning that it is subjective knowledge gained from relationship and not knowing objectively.
The only relationship God can have with us is one in which He is Lord. We can know Him no other way. We can know about Him, by reputation, in the mind rather than in the spirit. But to know Him in the sense in which the word is used here is to know Him as Lord; and to know Him thus, one must be utterly surrendered to His lordship. There is no other way to know Him that can give eternal life.
But there is also false life; this is the way of religion whereby you can know about God, know Him by reputation, but not as Lord to whom one is totally surrendered. This is to know God in the mind but not in the spirit. Only yielded believers can truly know God.
There is a false birth, a counterfeit of being born from above, which is to be born from below. Instead of receiving the Holy Spirit, the spirit of the world is received; this false new birth is a quickening of the soul, not the spirit, and so they cannot see the kingdom of God. “…unless one is born from above he is not able to see the kingdom of God” (John 3:3).
It is a real experience, nevertheless, this counterfeit of being born again from above, and can produce great zeal and commitment; look at Islam or Mormonism. But they are not born again into the kingdom of God, but into religion, which is a kingdom of this world; and they can never know God.
Jesus said that we may know false prophets from their fruits, and the principle applies generally. “Now the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, humility, self control” (Galatians 5:22-23). This is not the fruit of Islam, for example, nor is it the fruit of religious cults of any description.
The point to know is that this fruit cannot be counterfeited; it is of the Holy Spirit alone, Of course, people can pretend to be loving, kind, patient etc. but it is hard to pretend to have all of these qualities; and the fruit of the Spirit is singular; all of these qualities are included in the fruit.