Jesus has seen the state of the temple and it isn’t good. God judgement is going to strike it for its sorry state. But not yet. There must be mercy in wrath. Jesus will delay the destruction so that some may be saved. However, he still needs to show what lies ahead and so carefully plans an angry visit to the temple. With actions and words he exposes what sin has done to God’s house.
And here is a short talk based on the same passage: He Changed The World (Episode 46)