11 Bible Verses about Holiness,  Worldly Separation

Then again he called the crowd to him and said: "Listen to me, all of you, and understand; there is nothing outside a man which by entering in can defile him; but it is what comes from him that defiled him." OMITTED TEXT.read more.
After he had left the crowd and gone indoors his disciples began asking him about the parable. "Are even you without understanding?" he said. "Do you not perceive that nothing whatever from without can defile a man by entering him, because it does not go into his heart, but into his belly, and passes away, ejected from him?" By these words he pronounced all foods clean.

"Not so, my Lord," answered Peter, "for I have never yet eaten anything common and unclean."

"Men of Israel, help! This is the man who goes everywhere preaching to everybody against the people, and the Law, and this place. And he has actually brought Gentiles even into the temple, and has desecrated the holy place."

Any one who set at naught the law of Moses was put to death without pity, on the testimony of two or three witnesses. How much surer, think you, will be the punishment of one who has trodden under foot the Son of God, and has profaned that covenant blood with which he was sanctified, and has done despite to the spirit of grace?

But a man named Ananias who, with his wife Sapphira, sold a farm of his, kept back some of the purchase price, with the connivance of his wife. He brought only a part and laid it at the apostles' feet. "Ananias," said Peter, "why has Satan so filled your heart that you are lying to the Holy Spirit, and keeping back part of the price of the land?read more.
"While it remained unsold, was it not your own? And after it was sold, was not the price at your own disposal? How could you conceive this act in your heart? You have not lied unto men, but unto God." As Ananias heard these words he fell down and expired, and all who heard were awe-struck. But the younger men rose, wrapped the body up, and carried it out to bury it. About three hours later his wife came in, not knowing what had happened; and Peter said to her, "Tell me if you got so much for the land." "Yes," she said, "so much." "Why was it," said Peter, "that you both agreed to tempt the Spirit of the Lord? Lo, the feet of those who buried your husband are at the door, and they shall carry you out." Instantly she fell down at his feet and expired, and when the young men came in they found her dead, and carried her out and buried her husband.

"If you belonged to the world, the world would love its own; but because you do not belong to the world, but I have chosen you out of the world, for that reason the world hates you.

You adulteresses, do you not know that the friendship of the world is enmity to God? Whoever, then, desires to be a friend of the world, makes himself and enemy of God.

But you are an elect race, a royal priesthood, a holy nation, a purchased people, that you may show forth the virtues of Him who has called you out of darkness into his marvelous light??10 you who once were not a people, but now are the people of God; who were once without mercy, but now you have found mercy. I beseech you, beloved, as pilgrims and exiles, to abstain from passions of the flesh that war upon your souls.

I have given them thy word; and the world has hated them because they are not of the world, even as I am not of the world. I am not asking that thou wilt take them out of the world, but that thou wilt protect them from the Evil One. They are not of the world, even as I am not of the world.

Nevertheless God's firm foundation stands unshaken, bearing this inscription, THE LORD KNOWS THOSE WHO ARE HIS, and this also, LET EVERY ONE WHO NAMES THE NAME OF THE LORD RENOUNCE WICKEDNESS.

and undefiled before our God and Father, to look after orphans and widows in their affliction, and ever to keep himself unspotted from the world.