Ben Sira 12:11

11 Even if he humbles himself and walks bowed down, take care to be on your guard against him. Be to him like one who polishes a mirror, to be sure it does not become completely tarnished.

Ben Sira 12:11 In-Context

9 One's enemies are friendly when one prospers, but in adversity even one's friend disappears.
10 Never trust your enemy, for like corrosion in copper, so is his wickedness.
11 Even if he humbles himself and walks bowed down, take care to be on your guard against him. Be to him like one who polishes a mirror, to be sure it does not become completely tarnished.
12 Do not put him next to you, or he may overthrow you and take your place. Do not let him sit at your right hand, or else he may try to take your own seat, and at last you will realize the truth of my words, and be stung by what I have said.
13 Who pities a snake charmer when he is bitten, or all those who go near wild animals?
New Revised Standard Version Bible, copyright 1989, Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved.