Let me quote this very important passage of Scripture: Hebrews 11:1-3
"Now faith is the substance of things hoped for, the evidence of things not seen. For by it the elders obtained a good testimony. By faith we understand that the worlds were framed by the word of God, so that the things which are seen were not made of things which are visible."
So, this is the premise from which this book would be written. We cannot even begin to understand the Scriptures or the heart of God if we do not believe that He is. And to do that we must enact the faith that everyone of us were given at birth according to: Romans 12:3
Because God always existed, we must understand and believe that He existed outside of space and time in the realm called Eternal. I believe that this is why we could understand the following passage of Scripture: Matthew 25:34-40
So, He knew exactly what He was seeking to accomplish, and nothing could take Him by surprise.
And that time, as we know it only began when He created it. This was done when He created the Heavens and the earth as recorded in the book of Genesis, when He established the sun and the moon and day and night causing, the establishment of days and night, and the record of days.