God’s eternal nature is due a posteriori to his essence as existence. Further, His other qualities as immutable and infinite make him the only eternal being, as eternity belongs to Him alone.
What must be understood is that eternity does not share and is not the same thing as time, for God created and began time and is what our finite minds can conceive as “time” but not as a thing is created or born or began – God is outside all of these.
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