Complex sentence: This happens because, as far as the Auditors are concerned, to have a personality is to be a living being with a beginning and an end; the intervening time between them seems infinitely small to entities who have experienced eternity.
Split into simpler sentences: This happens because, as far as the Auditors are concerned, to have a personality is to be a living being with a beginning and an end. The intervening time between them seems infinitely small to entities who have experienced eternity.