Now the Passover of the Jews was at hand, and Jesus went up to Jerusalem. And He found in the temple those who sold oxen and sheep and doves, and the money changers doing business. When He had made a whip of cords, He drove them all out of the temple, with the sheep and the oxen, and poured out the changers' money and overturned the tables. And He said to those who sold doves, "Take these things away! Do not make My Father's house a house of merchandise!" John 2:13-16
Temple is a place for people to come and meet God. Temple is a place where God dwells. So when you come to a temple you come and worship! But during this time of Passover, the temple lost its function and it turned into a market for personal profit! Think of how sad God would have been when He was waiting for His people to come and spend time with Him, but instead they were only interested in making money for themselves.
God tells us that our body is the temple of the Holy Spirit. Our body is a place where the Holy Spirit dwells. It is sacred and important. The above text tells us how important it is for us to take care of ourselves. God wants to dwell among us. He wants to spend time with us. We need to practice in thinking Godly things, not worldly things. It's important for us to make sure that we gain on Godly matters, not selfish personal matters.