Jesus enters the temple and clears it. Mark and Luke also record the same incident. John records another temple cleansing incident in John 2:13-17, so Jesus probably cleared the temple twice.
The temple was full of money changers and those selling doves. They were doing this because people came from far and wide, and the traders sold doves so that the worshipers could offer these as a sacrifice. So why did Jesus object to this practice which was there to help them worship God? Well perhaps the trading had become the focus rather than the worship. We need to be very careful that we do not fall into the same trap.
Immediately after this we see Jesus put into practice the true worship when He heals the sick. The church is to be a supernatural entity. This does not mean we ignore common sense and practicalities, but we should be marked by the presence of God. And when God is present things happen: people are healed, lives are changed.
The children shouted out praise to Jesus when they saw the healings, but the priests were indignant. Jesus quotes from Psalm 8:2. The religious authorities had lost all idea of what worship and life with God was all about.