Tafsir of Ash-Shu`ara' 26:26

(He said) — shifting to that which is clearer and closer to giving the position of guidance its due, as far as possible, since grasping the [absolute] reality is impossible, as you have heard: (Your Lord and the Lord of your first forefathers).

For origination and the state of need for a Necessary, Formative, Wise Creator are more apparent in the addressees and their forefathers who have departed and ceased to exist; and reflection upon one's own self is closer and clearer than reflection upon the horizons [of the universe]. When the accursed one saw that, and the fear of his people being swayed [from their disbelief] became strong within him...