Numbers 6:5 All the days of the vow of his separation there shall no razor come upon his head: until the days be fulfilled, in the which he separateth himself unto the LORD, he shall be holy, and shall let the locks of the hair of his head grow.
  6 All the days that he separateth himself unto the LORD he shall come at no dead body.

Proverbs 16:28 A froward man soweth strife: and a whisperer separateth chief friends.
17:9 He that covereth a transgression seeketh love; but he that repeateth a matter separateth very friends.

Ezekiel 14:7 For every one of the house of Israel, or of the stranger that sojourneth in Israel, which separateth himself from me, and setteth up his idols in his heart, and putteth the stumblingblock of his iniquity before his face, and cometh to a prophet to enquire of him concerning me; I the LORD will answer him by myself: