By nature we don't even know we have a need. It's only when we are face to face with God in Christ that the Holy Spirit graciously opens our eyes, and we see that "we come short of the glory of God".
And now, through the death of Christ, on behalf of us sinners, God has provided the forgiveness and cleansing, fullness and fruit for God.
It is a life of constant "beholding him", which teaches us wisdom - of knowing the God of fullness and knowing the emptiness of self.
And faith is the hand that appropriates the fullness of God to our empty selves.