This psalm is desparately looking for a truth to hold on to as the world is burning. The setting is the destruction of the temple, placing it somewhere in the timeframe of the early Babylonian Exile. Jerusalem has been ransacked. God's temple was looted and burned. Israel is under the subjugation of a cruel enemy.
It is in this awful experience that Asaph does three important things. First, he inventories and acknowledges the painful losses. Top on the list is the temple of God in ruins. He is appalled at the sight of it. The spiritual damage is so intense that even the voices of the prophets have ceased. Confusion and silence mark the grief of the survivors.
The second thing that Asaph does is to recall the mighty power of The Lord. He spends the latter half of the psalm describing God's mighty works. He centers on two levels of God's activity: His creative work AND His works of deliverance for His people. This is a way of regaining perspective. He knows Who God is and he knows what God does. Present circumstances do not change Who God is nor do they obliterate the truth of the past salvation God has brought.
From there, the third part of this psalm cries out again to God for salvation. These prayers are interspersed throughout the song. But they are most powerfully made at the end, when faith looks to the character of God, surveys His past power, and then trusts God to change the pain into something that shows His power and His glory.