Genesis 1:1, the first verse in the Bible, begins with "In the beginning, God...". This verse is often passed over quickly to read the story of creation. But it is important. It teaches us a great truth.
God existed before he created the earth. When it says "in the beginning", and "he created", it means God existed before the earth. He is eternal, not beginning or ending. He did not come into being upon the formation of the earth. He was always there, he then created earth. He has always existed, the earth has not.
Christ, the second person of the Trinity, also is eternal. John 1:1 tells us this. John wrote: "In the beginning was the Word". In John 1, "Word" refers to Christ. Jesus declared his eternal existence while praying in John 17:5, "And now, Father, glorify me in your own presence with the glory that I had with you before the world existed".
The Holy Spirit, the third person of the Trinity, is also eternal. In Genesis 1:2, the Spirit of God was hovering over the face of the waters. God, in the unity of the Trinity, existed before the earth was created.
Other scriptures declare the eternal existence of God. In Isaiah 44:6, God declared:
Thus says the LORD, the King of Israel
and his Redeemer, the LORD of hosts:
I am the first and I am the last;
besides me there is no god.
God is eternal. He was here before us. He will always be. We did not invent him, he created us. No matter how long our life on earth remains, it will end. He will not. When our flesh releases our spirit, he will be there to receive it. (Ecclesiastes 9:7)