From my reading “The Attributes of God” by the eminently quote-worthy A. W. Pink :
Before all else “In the beginning God” (Gen 1:1). There was a time, if “time” it could be called, when God, in the unity of His nature (though subsisting equally in three divine persons), dwelt all alone. “In the beginning God.” There was no heaven, where His glory is now particularly manifested. There was no earth to engage His attention. There were no angels to hymn His praises; no universe to be upheld by the word of His power. There was nothing, no one, but God; and that, not for a day, a year, or an age, but “from everlasting.” During eternity past, God was alone: self-contained, self-sufficient, self-satisfied; in need of nothing. Had a universe, had angels, had human beings been necessary to Him in any way, they also had been called into existence from all eternity. The creating of them when He did, added nothing to God essentially. He changes not (Mal 3:6), therefore His essential glory can be neither augmented nor diminished.
Pink, Arthur W. (2010-04-05). The Attributes of God (Kindle Locations 67-76). Unknown. Kindle Edition.