These are two powerful, succinct sentences. It is a prayer to the Lord. Arise, Lord, do not leave the power to the people. They cannot maintain or execute justice. They are too weak and too sinful for that. Let the nations be judged by you. Let them appear before you, as the highest and holy Judge, only then things will work out well.
Put them in fear, O Lord. Let them have so much respect for you, Lord, that they will not try to be their own judge. Their pride comes to nothing. That would amount to rebellion against the name of the Lord, and it will go wrong. When they realize that they are merely people, then they know their place and will not do any crazy things. To know your place is always a good thing.
The call to the Lord to arise
makes us think of the journey through the wilderness, for example, Numbers 10:35 “And whenever the ark set out, Moses said, “Arise, O Lord, and let your enemies be scattered, and let those who hate you flee before you.”
It is sometimes assumed that previously Psalm 9 and Psalm 10 were one. The accent in Psalm 9 is: God is righteous, and in Psalm 10:1–18 it is: the Lord waits to act. There is also a parallel when we compare Psalm 9:10 with Psalm 10:12–13 “Arise, O Lord; O God, lift up your hand; forget not the afflicted. Why does the wicked renounce God and say in his heart, You will not call to account
”?
19 Arise, O LORD! Let not man prevail; let the nations be judged before you!