1 Corinthians 10:15-18
15-18I assume I'm addressing believers now who are mature. Draw your own conclusions: When we drink the cup of blessing, aren't we taking into ourselves the blood, the very life, of Christ? And isn't it the same with the loaf of bread we break and eat? Don't we take into ourselves the body, the very life, of Christ? Because there is one loaf, our many-ness becomes one-ness—Christ doesn't become fragmented in us. Rather, we become unified in him. We don't reduce Christ to what we are; he raises us to what he is. That's basically what happened even in old Israel—those who ate the sacrifices offered on God's altar entered into God's action at the altar.
19-22Do you see the difference? Sacrifices offered to idols are offered to nothing, for what's the idol but a nothing? Or worse than nothing, a minus, a demon! I don't want you to become part of something that reduces you to less than yourself. And you can't have it both ways, banqueting with the Master one day and slumming with demons the next. Besides, the Master won't put up with it. He wants us—all or nothing. Do you think you can get off with anything less?