Some issues are not as neat as others. The Israelites were now a free people and needed to act responsibly socially as well as consider their dealings with life and property. The way they dealt with sex, idolatry and sorcery could have long term implications as they entered Canaan where those things were both present and prevalent.
God called his people to be different. They were to act in an appropriate way, even when the inappropriate was legal. Witchcraft, sorcery, inappropriate sexual relationships all destroyed the culture and the ability to worship God and be selfless. That is why God said no.
In our culture, we are called to be different as well. There are many things our culture allows—that are simply inappropriate. When we live our lives, we have to live in a way that honors God. If the things that we do dishonor him, their legality becomes unimportant. God said it best, “Trust in the Lord with all your heart, lean not on your own understanding in all your ways acknowledge him and he will make your paths straight.” Proverbs 3:5-6
God Bless You
“If a man seduces a virgin who is not pledged to be married and sleeps with her, he must pay the bride-price, and she shall be his wife. 17 If her father absolutely refuses to give her to him, he must still pay the bride-price for virgins.
18 “Do not allow a sorceress to live.
19 “Anyone who has sexual relations with an animal is to be put to death.
20 “Whoever sacrifices to any god other than the Lord must be destroyed.[e]
21 “Do not mistreat or oppress a foreigner, for you were foreigners in Egypt.
22 “Do not take advantage of the widow or the fatherless. 23 If you do and they cry out to me, I will certainly hear their cry. 24 My anger will be aroused, and I will kill you with the sword; your wives will become widows and your children fatherless.