Psalm 4

Ps 4:1 Hear me when I call, O God of my righteousness!
You have relieved me in my distress; Have mercy on me, and hear my prayer.
:2 How long, O you sons of men, will you turn My glory to shame? How long will you love worthlessness and seek falsehood? Selah
:3 But know that the Lord has set apart for Himself him who is godly; the Lord will hear when I call to Him.
:4 Be angry, and do not sin. Meditate within your heart on your bed, and be still. Selah
:5 Offer the sacrifices of righteousness, and put your trust in the Lord.
:6 There are many who say, "who will show us any good?" Lord, lift up the light of Your countenanace upon us.
:7 You have put gladness in my heart, more then in the season that their grain and wine increased.
:8 I will both lie down in peace, and sleep; for You alone, O Lord, make me dwell in safety.

Sacrifices of righteousness are those offered with the right attitude.

Verse 4 tells us to be angry and sin not. Are you ever angry with God because you feel you know exactly how He should handle something you are praying about and yet that is not what He does? Do you think if during that time you offered what you think is sacrifices of righteousness He would accept them? We must be willing to accept God's answer to our prayers even when we don't agree with the answer He has.