1Now I would not have you ignorant, brothers, that our fathers were all under the cloud, and all passed through the sea; 2and were all baptized into Moses in the cloud and in the sea; 3and all ate the same spiritual food; 4and all drank the same spiritual drink. For they drank of a spiritual rock that followed them, and the rock was Christ. 5However with most of them, God was not well pleased, for they were overthrown in the wilderness.
6Now these things were our examples, to the intent we should not lust after evil things as they also lusted. 7Don’t be idolaters, as some of them were. As it is written, “The people sat down to eat and drink, and rose up to play.” 8Let’s not commit sexual immorality, as some of them committed, and in one day twenty-three thousand fell. 9Let’s not test Christ, as some of them tested, and perished by the serpents. 10Don’t grumble, as some of them also grumbled, and perished by the destroyer. 11Now all these things happened to them by way of example, and they were written for our admonition, on whom the ends of the ages have come. 12Therefore let him who thinks he stands be careful that he doesn’t fall.
13No temptation has taken you except what is common to man. God is faithful, who will not allow you to be tempted above what you are able, but will with the temptation also make the way of escape, that you may be able to endure it.
14Therefore, my beloved, flee from idolatry. 15I speak as to wise men. Judge what I say. 16The cup of blessing which we bless, isn’t it a sharing of the blood of Christ? The bread which we break, isn’t it a sharing of the body of Christ? 17Because there is one loaf of bread, we, who are many, are one body; for we all partake of the one loaf of bread. 18Consider Israel according to the flesh. Don’t those who eat the sacrifices participate in the altar?
19What am I saying then? That a thing sacrificed to idols is anything, or that an idol is anything? 20But I say that the things which the Gentiles sacrifice, they sacrifice to demons and not to God, and I don’t desire that you would have fellowship with demons. 21You can’t both drink the cup of the Lord and the cup of demons. You can’t both partake of the table of the Lord and of the table of demons. 22Or do we provoke the Lord to jealousy? Are we stronger than he?
23“All things are lawful for me,” but not all things are profitable. “All things are lawful for me,” but not all things build up. 24Let no one seek his own, but each one his neighbor’s good. 25Whatever is sold in the butcher shop, eat, asking no question for the sake of conscience, 26for “the earth is the Lord’s, and its fullness.” 27But if one of those who don’t believe invites you to a meal, and you are inclined to go, eat whatever is set before you, asking no questions for the sake of conscience. 28But if anyone says to you, “This was offered to idols,” don’t eat it for the sake of the one who told you, and for the sake of conscience. For “the earth is the Lord’s, with all its fullness.” 29Conscience, I say, not your own, but the other’s conscience. For why is my liberty judged by another conscience? 30If I partake with thankfulness, why am I denounced for something I give thanks for?
31Whether therefore you eat or drink, or whatever you do, do all to the glory of God. 32Give no occasion for stumbling, whether to Jews, to Greeks, or to the assembly of God; 33even as I also please all men in all things, not seeking my own profit, but the profit of the many, that they may be saved.
Deut 12:2 "Ye shall utterly destroy (חרם, ḥērem)" -Israel is supposed to be totally separate culture from those around them.
The passage here is much about the centralization of worship in Deuteronomy, and as such a very important topic in academic discussion in Old Testament scholarship for the last 200 years. Without going here into any of the complications and various opinions expressed, according to Deuteronomy’s vision, Israel is to gather together in one place for worship three times a year, and sacrifice their offerings only in that place. In a broader context, this is to happen when the nation has settled in the land and is at peace, and such travelling is possible in practice (Deuteronomy 12:10-11). In other circumstances, one may sacrifice locally (cf. Exodus 20:22-24; cf. Deuteronomy 27; Joshua 8:30-35; note however that, according to Leviticus 17:1-9, during the time in the wilderness, all sacrifices had to be brought to the tent of meeting, the Israelite sanctuary at the time). In a yet broader context, the concern of Deuteronomy, and the Pentateuch and Old Testament as a whole is that the Israelites worship only their God Yahweh. From another angle, as part of the settlement and striving towards purity in life and worship, the indigenous nations and their worship practices are to be eradicated so that no trace is left to lead Israel astray.
In modern thinking, the command in Deuteronomy actually amounts to genocide and is therefore problematic, particularly for those who take a high view of Scripture, and raises the question of theodicy, or the justification of God’s actions. But, if one reads the book of Revelation or even the New Testament as a whole, the apparent concept of damnation to unbelievers is at least arguably in line with the concept of killings of non-Yahwists in the Israelite conquest tradition. The issue at hand here is also perhaps mitigated by the fact that the Israelites did not manage to drive out or kill many of the native inhabitants, and by the fact that the conquest and settlement are to be considered as a one-time non-repeatable set of events.
All this said, as the nations were left in the land, as the Bible describes, the Israelites started to follow their practices (see the book of Judges in particular). These points considered, for Christians the passage can be read to promote fleeing away from idolatry and from any practices that are contrary to good Christian ethical principles, in line with New Testament material (cf. 1 Corinthians 10:14). The New Testament also seems to ask Christians to think of whom they associate with (1 Corinthians 15:33), and yet, this does not mean that one cannot associate with those who are not Christian (1 Corinthians 5:9-11). Jesus himself associated with all, and the Pharisees who criticised him for that are described as hypocrites by the New Testament (see e.g. Matthew 9:9-13, 22:18, note also that Paul in 1 Corinthians 15:33 might be quoting a popular proverb of the time). So, great wisdom and humility is required of Christians in following God with joy and ethical verve, while at the same time refraining from dubious practices without becoming haughty, condescending, or even violent towards others.