The scripture that best explains this is found in Colossians 1:12-18, “Giving thanks unto the Father, which hath made us meet to be partakers of the inheritance of the saints in light…Who is the image of the invisible God, the firstborn of every creature: For by him were all things created, that are in heaven, and that are in earth, visible and invisible, whether they be thrones, or dominions, or principalities, or powers: all things were created by him, and for him: And he is before all things, and by him all things consist. And he is the head of the body, the church: who is the beginning, the firstborn from the dead; that in all things he might have the preeminence.”
The concept of firstborn is of one having a beginning coming from another that was prior to himself but is the first of perhaps many. The same concept is also stated in Revelation 3:14, “And unto the angel of the church of the Laodiceans write; These things says the Amen, the faithful and true witness, the beginning of the creation of God.” This says that the very first thing that God did while being alone was to create Jesus.
Another scripture passage that says the same thing is found in Proverbs 8:22-23 (Revised Standard Version), “The LORD created me at the beginning of his work, the first of his acts of old. Ages ago I was set up, at the first, before the beginning of the earth.” Although this is talking about wisdom, consider 1 Corinthians 1:30, “But of him are ye in Christ Jesus, who of God is made unto us wisdom.” Hence Proverbs 8 is talking about Jesus, who is the wisdom of God in his pre-human experience.
Most translators follow the Latin Vulgate mistranslation for John 1:1 rather than John’s original Greek! John literally tells us that the Word (Jesus before becoming a babe in Bethlehem) was “towards God.” This requires some interpretation.
Hebrews 2:17 provides insight; “Therefore, He (Jesus) had to be made like His brethren, that he might be a merciful and faithful high priest in things pertaining to God….” This Greek phrase “in things pertaining to God” and “with God” are identical! Clearly, their sense is “to be in heart union and desiring to serve.”
John carefully tried to distinguish our Heavenly Father (“the God”) from his son, our Lord Jesus – the Word – who was “a god.” Again, translators have created confusion. Literally, John 1:1 reads, “In the beginning was the Word and the Word was towards the God and a god was the Word, this was in the beginning with the God.” Jesus as a mighty archangel was “a god,” not his Heavenly Father, “the God.” Jesus has always desired to serve our Heavenly Father.