A RIGHTEOUS ENEMY OR A CORRUPT FRIEND?
Sufyān bin 'Uyainah (رحمه الله) would say:
"For you to have a righteous enemy is better than for you to have a corrupt friend, because the righteous enemy - his Ēmān obstructs him from harming you - or that he should impair upon you that which you dislike, whilst the corrupt friend does not care concerning that which is impaired from you."*
* Hilyatul Awliyā vol 7 p. 281
Book: The Perfume-Seller & the Blacksmith Concise Words on Good and Bad Companionship
Salafi Publications
P. 55