The psalmist envisaged an abundance of water in Jerusalem through a river. (Psalm 46:4) There was no river, only streams in Jerusalem. However, he was looking towards the river flowing from the temple as Ezekiel prophesied. (Ezekiel 47:12; Revelation 22:1) The psalmist was looking towards the millennial rule of the Messiah. Believers today enjoy the Kingdom in the Holy Spirit. (Romans 14:17)
Live-giving water: The river makes the city glad because it brings live-giving water to dry land. The Lord Jesus Christ explained that those who believe will have the Living waters in them, meaning the person of the Holy Spirit indwelling in them. (John 14:27)
Many streams: The river psalmist foresaw many streams. It is similar to the rivers that watered the Garden of Eden. (Genesis 2:10-14)
Peace: River also indicates peace. (Isaiah 48:18; 66:12) The city would be the city of peace. The Lord promised peace, that the world can neither give nor take away from a believer. (John 14:27)
Justice: Amos writes that justice ought to flow on like a river and righteousness like a never-failing stream. (Amos 5:24) The city of God is built on truth, justice, and righteousness.
Best defence: When enemies attacked, the city that had a river had a guaranteed water supply. Hence, withstand the attack of enemies. There will not be any lack, and will have complete protection.
Holy: The rivers make it glad because it is the Holy city where the Holy sanctuary, the Tabernacle of the Most High, is. The King of Kings and the Lord of Lords would reign in holiness.
God in the midst: The Psalmist sings that God is in the midst, hence the city will not be moved. The Messiah, seated on the throne of David, reigns and judges the world.
Bright Light: The city will enjoy the bright light of Jehovah just at the break of dawn. Nations may rage, but God does not pay attention to them and will judge them for rejecting the Son enthroned by the Father. (Psalm 2:10-12)
Do I enjoy the indwelling Holy Spirit of gladness?