He came home, and his guests were misusing his Father’s house. I suppose if you hired someone to watch your home while you were gone, you would have a certain expectation of what your home is to look like when you return. Christ came to his Father’s house and the way people were using his Father’s house was not as expected. Christ, therefore, had to clean house:

“The Passover of the Jews was near, and Jesus went up to Jerusalem. And He found in the temple those who were selling oxen and sheep and doves, and the money changers seated at their tables. And He made a scourge of cords, and drove them all out of the temple, with the sheep and the oxen; and He poured out the coins of the money changers and overturned their tables; and to those who were selling the doves He said, “Take these things away; stop making My Father’s house a place of business.” (John 2:13–16, NASB95)