Psalm 13 (NIV) 
For the director of music. A Psalm of David.
1 How long, Lord? Will you forget me forever?
    How long will you hide your face (Note: the presence of the Divine Spirit) from me?
2 How long must I wrestle with my thoughts
    and day after day have sorrow in my heart?
    How long will my enemy triumph over me? (Note: the greatest enemy is unbelief)
3 Look on me and answer, Lord my God.
    Give light to my eyes, or I will sleep in death, (Note: see "Light" Psalm 119: 130)
4 and my enemy will say, “I have overcome him,”
    and my foes will rejoice when I fall.
5 But I trust in your unfailing love; (Note: unfailing love of the Divine is unfolded by the Spirit of Understanding) 
    my heart rejoices in your salvation.
6 I will sing the Lord’s praise,
    for he has been good to me (Note: Seeing His goodness all the time is the sign of spiritual maturity )