What is important to believe is that Jesus did not pre-exist in heaven as God.
To teach that Jesus pre-existed in heaven as God is FALSE because it makes Jesus a LIAR who said that the Father is the ONLY TRUE God (John 17:3).
Jesus says he is a MAN (John 8:40). Apostle Paul also says Jesus is a MAN (1 Tim. 2:5; Acts 17:31; Rom. 10:9). The prophet David also says Jesus is a MAN (Psalm 80:17 c.f. Col. 3:1). Jesus says the Father is the ONLY TRUE God (John 17:3). Apostle Paul says there is ONLY ONE God, the Father (Eph. 4:6). The prophet Malachi says ONE God created us all (Mal. 2?:10).
Therefore, to TWIST John 6;38 to mean that Jesus pre-existed as God in heaven is a desperate and futile attempt to make Jesus God.