I used to think that all the chapters in the book of Psalms were written by David. When in fact, quite a few of the chapters are written by others. Psalm 89 is written by Ethan, the Esrahite. Some Bible scholars think he might have been one of the musicians in the court.
“I will sing of the Lord’s unfailing love forever! Young and old will hear of your faithfulness. Your unfailing love will last forever. Your faithfulness is an enduring as the heavens.” (vv 1-2) NLT
“All heaven will praise Your great wonders, Lord; myriads of angels will praise You for Your faithfulness. For who in all heaven can compare with the Lord? What mightiest angel is anything like the Lord? The highest angelic powers stand in awe of God. He is far more awesome than all who surround His throne. O Lord God of Heaven’s Armies! Where is there anyone as mighty as You, O Lord? You are entirely faithful.” (vv. 5-8) NLT
“Happy are those who hear the joyful call to worship, for they will walk in the light of Your presence, Lord They rejoice all day long in Your wonderful reputation. They exult in your righteousness. Your are their glorious strength. It pleases You to make us Strong.”(vv. 15-17) NLT
“Praise the Lord forever! Amen and amen!” (v. 52) NLT