To admit the existence of a need in God is to admit incompleteness in the divine Being. Need is a creature-word and cannot be spoken of the Creator. God has a voluntary relation to everything He has made, but He has no necessary relation to anything outside of Himself. His interest in His creatures arises from His sovereign good pleasure, not from any need those creatures can supply nor from any completeness they can bring to Him who is complete in Himself…

So lofty is our opinion of ourselves that we find it quite easy, not to say enjoyable, to believe that we are necessary to God. But the truth is that God is not greater for our being, nor would He be less if we did not exist. That we do exist is altogether of God’s free determination, not by our desert nor by divine necessity.

-A.W. Tozer, Knowledge of the Holy, p.52-53