Bob Hurd’s setting of Psalm 42 is rightly popular. As with many psalms, the writer is struggling with a sense of the absence of God in time of great need, which is then resolved ultimately in the relief of knowing that God is always present, it is only we ourselves that prevent us be aware of him. Here are some verses from the NRSV translation:
Deep calls to deep
at the thunder of your cataracts;
all your waves and your billows
have gone over me.
By day the LORD commands his steadfast love,
and at night his song is with me,
a prayer to the God of my life.
Why are you cast down, O my soul,
and why are you disquieted within me?
Hope in God; for I shall again praise him,
my help and my God.