Albert Barnes Commentary Psalms 89:43

"Yea, thou turnest back the edge of his sword, And hast not made him to stand in the battle." — Psalms 89:43 (ASV)

You have also turned the edge of his sword - That is, You have turned it away, so that when it is raised to strike, it does not descend on the object aimed at by the blow. The meaning is, that he had not been successful in battle, or had been defeated.

And have not made him to stand in the battle - To stand firm; to hold his ground. He has been driven back; his forces have fled.