A phrase commonly used to imply that the body is sacred and thus should be cared for by paying close attention to health and nutrition should not be defiled with things like drug use, fornication or even neglect. - It was even quoted to me once as a reason for not getting a tattoo.

The origin of the phrase seems to be a passage from the Bible - Corinthians 6:19-20 to be exact:

Do you not know that your body is a temple of the Holy Spirit, who is in you, whom you have received from God? You are not your own; you were bought at a price. Therefore honor God with your body

However it is now often used in a more non-specifically spiritual sense and interestingly is often associated with the Eastern Religions

Anyway I say bullshit - the body is a playground