11 Bible Verses about Holiness,  Worldly Separation

He called the people to him again and said to them, "Listen to me, all of you, and understand this. Nothing that goes into a man from outside can pollute him. It is what comes out of a man that pollutes him." OMITTED TEXTread more.
When he had left the crowd and gone home, his disciples asked him what he meant by this figure. And he said to them, "Have not even you any understanding then? Do you not see that nothing that goes into a man from outside can pollute him, since it does not go into his heart but into his stomach and then is disposed of?" So he declared all food clean.

But Peter said, "Never, sir! For I have never eaten anything that was not ceremonially cleansed."

shouting, "Men of Israel, help! This is the man who teaches everybody everywhere against our people and the Law and this place, and besides he has actually brought Greeks into the Temple and desecrated this sacred place."

Anyone who breaks the Law of Moses is put to death without any show of pity, on the evidence of only two or three witnesses. How much worse a punishment do you think will anyone deserve who tramples the Son of God underfoot, and treats as worthless the blood of the agreement by which he has been purified, and outrages God's spirit of mercy?

But a man named Ananias, who, with his wife Sapphira, had sold a piece of property, with his wife's connivance appropriated some of the price received, and brought only a part of it to put at the disposal of the apostles. And Peter said, "Ananias, why has Satan taken such possession of your heart that you should lie to the holy Spirit, by appropriating part of the price of your land?read more.
As long as it was unsold was it not yours, and after it was sold was not the money under your control? How could you think of doing such a thing? You did not lie to men but to God!" When Ananias heard these words he fell down and expired, and everyone who heard them spoken was appalled. The younger men got up and wrapping his body up carried it out and buried it. About three hours later, his wife came in, without having learned what had happened. Peter said to her, "Tell me, did you sell the land for such and such a sum?" "Yes," she said, "that was it." Peter said to her, "How could you two agree to test the Spirit of the Lord? There at the door are the footsteps of the men who buried your husband, and they will carry you out also." She instantly fell down at his feet and expired. When the young men came in they found her dead, and they carried her out and buried her beside her husband.

If you belonged to the world, the world would love what was its own. But it is because you do not belong to the world, but I have selected you from the world, that the world hates you.

You renegades! Do you not know that the friendship of the world means enmity with God? So whoever wishes to be the world's friend declares himself God's enemy.

But you are the chosen race, the royal priesthood, the consecrated nation, his own people, so that you may declare the virtues of him who has called you out of darkness into his wonderful light; you who were once "no people" but are now "God's people"; once "unpitied" but now "pitied indeed." Dear friends, I beg you, as aliens and exiles here, not to indulge the physical cravings that are at war with the soul.

I have given them your message, and the world has come to hate them, for they do not belong to the world any more than I belong to the world. I do not ask you to take them away from the world, but to keep them from evil. They do not belong to the world any more than I belong to the world.

Yet God's solid foundation stands unshaken, bearing this inscription, "The Lord knows those who belong to him," and "Everyone who uses the name of the Lord must give up evil."

A religious observance that is pure and stainless in the sight of God the Father is this: to look after orphans and widows in their trouble, and keep one's self unstained by the world.