you asked for Biblical references, and I gave you one. It’s understanding the context. It doesn’t make sense that God has always and will always exist. But if God existed in time that would imply that time created God, wouldn’t it? It implies a beginning to God, which we believe there was no beginning with God, because he always exists. If God existed in time then time came before God.
No one truly understands this concept except those with God in heaven perhaps. We understand that it is true but not how it is true.
here’s another verse I found, the one I was actually thinking of at that time but didn’t remember how it started.
“In the beginning was the Word, and the Word was with God, and the Word was God”. John 1:1