Psalms 4

^{This Psalm is unusual. The Living Bible paraphrase confirms my opinion: It is a conversation between David and God. It begins with David crying out for God to hear his prayer
1}Answer me when I call to you,
    my righteous God.
 Give me relief from my distress;
    have mercy on me and hear my prayer.

In the next section God calls the people, and apparently David, to account for their neglect of praise and worship.

² How long will you people turn my glory into shame?
    How long will you love delusions and seek false gods^[b]?^[c]

In Verse 3 David  claims God's provision for himself joins in God's reproof.

³ Know that the Lord has set apart his faithful servant for himself;
    the Lord hears when I call to him.

In Verse 4 he refers to how the quality of sleep is affected by the spiritual condition.
 

⁴ Tremble and^[d] do not sin;
    when you are on your beds,
    search your hearts and be silent.

In verse 5 I can't tell whether it is David or God that calls us to offer "righteous sacrifices," but in either case we are counseled to "trust in the Lord." 

⁵ Offer the sacrifices of the righteous
    and trust in the Lord.

In Verse 6 the speaker is David.  He knows that God is our only help in times of difficulty and he seeks the light of his face.
 

⁶ Many, Lord, are asking, “Who will bring us prosperity?”
    Let the light of your face shine on us.

 

 

 It is God's joy David seeks more than the sustenance of grain or the refreshment of wine.

⁷ Fill my heart with joy
    when their grain and new wine abound.

David again refers to the sustaining nature of peaceful sleep being assured that God provides for his safety.
 

⁸ In peace I will lie down and sleep,
    for you alone, Lord,
    make me dwell in safety.