Prior to creation there must exist a unity, which is beyond form and eternal. To posit the idea of duality, or the existence of more than one god, is to assume division. But division can only occur from unity, which means that unity precedes division. The first state is, therefore, one of unity.
For one God to exist as the supreme and eternal being, His existence must be beyond space and time. An infinite God, outside of space and time, cannot share existence with another. To my understanding, as soon as division, or creation, occurs, you get space and time.