Sir 12:8 A friend shall not be known in prosperity, and an enemy shall not be hidden in adversity.
Sir 12:9 In the prosperity of a man, his enemies are grieved: and a friend is known in his adversity.
Sir 12:10 Never trust thy enemy for as a brass pot his wickedness rusteth:
Sir 12:11 Though he humble himself and go crouching, yet take good heed and beware of him.
Sir 12:12 Set him not by thee, neither let him sit on thy right hand, lest he turn into thy place, and seek to take thy seat and at the last thou acknowledge my words, and be pricked with my sayings.
Sir 12:13 Who will pity an enchanter struck by a serpent, or any that come near wild beasts? so is it with him that keepeth company with a wicked man, and is involved in his sins.
Sir 12:14 For an hour he will abide with thee: but if thou begin to decline, he will not endure it.
Sir 12:15 An enemy speaketh sweetly with his lips, but in his heart he lieth in wait, to throw thee into a pit.
Sir 12:16 An enemy weepeth with his eyes: but if he find an opportunity he will not be satisfied with blood:
Sir 12:17 And if evils come upon thee, thou shalt find him there first.
Sir 12:18 An enemy hath tears in his eyes, and while he pretendeth to help thee, will undermine thy feet.
Sir 12:19 He will shake his head, and clap his hands, and whisper much, and change his countenance.
I believe this is all about not being friends with bad people. It doesn’t turn out well for you. Of course we are called to be kind to all and especially try to lead them to Christ, but if you know someone is a thief and you let them into your house and don’t watch them, don’t be surprised if they steal.