In Paul's day there were temples to false gods, dead gods, which he contrasts with the temple of the living God. The living God lives in a living temple, not in a building filled with statues of false gods, whether Roman or Greek. The living God chooses living temples, and that is who we are. Not only did God live with us and walk among us, he continues to do so in believers today.
Further we should be separate from those who worship false gods (vs 17) and purify ourselves from anything that contaminates either body or spirit (vs 18). Paul said this because he knew how difficult it was to live surrounded by non-believers. It is easy to be contaminated by unbelief, by worldly ideas, by false gods, unless we are strengthened by the Holy Spirit
For Reflection: Am I entangled with false gods or unbelievers in ways that I shouldn't be? Have I been contaminated?
Let us pray. Jesus, let me in to your decontamination unit. I want to be wholly yours.