Yes, its OK:
"Therefore concerning the eating of the things sacrificed to idols, we know that an idol is nothing...food will not commend us to God; neither if we should eat do we come short...
1 Cor 8
No, its not OK:
"That what is sacrificed to an idol is anything, or that an idol is anything? Rather, that what the Gentiles sacrifice, they sacrifice to demons and not to God. And I do not want you to be fellow partakers with demons."
1 Cor 10
"teaching and misleading My servants to commit sexual immorality and to eat things sacrificed to idols..."
Rev 2:20
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And a smaller question, how is the weak brother destroyed?
...for the one being weak is destroyed through your knowledge." 1 Cor 8
1 Corinthians 8:4-13
4 So then, about eating food sacrificed to idols: We know that “An idol is nothing at all in the world” and that “There is no God but one.” 5 For even if there are so-called gods, whether in heaven or on earth (as indeed there are many “gods” and many “lords”), 6 yet for us there is but one God, the Father, from whom all things came and for whom we live; and there is but one Lord, Jesus Christ, through whom all things cameand through whom we live.
7 But not everyone possesses this knowledge. Some people are still so accustomed to idols that when they eat sacrificial food they think of it as having been sacrificed to a god, and since their conscience is weak, it is defiled. 8 But food does not bring us near to God; we are no worse if we do not eat, and no better if we do.
9 Be careful, however, that the exercise of your rights does not become a stumbling block to the weak. 10 For if someone with a weak conscience sees you, with all your knowledge, eating in an idol’s temple, won’t that person be emboldened to eat what is sacrificed to idols? 11 So this weak brother or sister, for whom Christ died, is destroyed by your knowledge.12 When you sin against them in this way and wound their weak conscience, you sin against Christ. 13 Therefore, if what I eat causes my brother or sister to fall into sin, I will never eat meat again, so that I will not cause them to fall.