The Quran

۞ يا أَيُّهَا الَّذينَ آمَنوا لا تَتَّبِعوا خُطُواتِ الشَّيطانِ ۚ وَمَن يَتَّبِع خُطُواتِ الشَّيطانِ فَإِنَّهُ يَأمُرُ بِالفَحشاءِ وَالمُنكَرِ ۚ وَلَولا فَضلُ اللَّهِ عَلَيكُم وَرَحمَتُهُ ما زَكىٰ مِنكُم مِن أَحَدٍ أَبَدًا وَلٰكِنَّ اللَّهَ يُزَكّي مَن يَشاءُ ۗ وَاللَّهُ سَميعٌ عَليمٌ

Muhammad Asad

O YOU who have attained to faith! Follow not Satan's footsteps: for he who follows Satan's foot steps [will find that], behold, he enjoins but deeds of abomination and all that runs counter to reason.¹ And were it not for God's favour upon you and His grace, not one of you would ever have remained pure.For [thus it is:] it is God who causes whomever He wills to grow in purity: for God is all-hearing, all-knowing.

In this context, the term al-munkar has apparently the same meaning as in 16:90 (explained in the corresponding note 109) since, as the sequence shows, it clearly relates to the unreasonable self-righteousness of so many people who "follow Satan's footsteps" by imputing moral failings to others and forgetting that it is only due to God's grace that man, in his inborn weakness, can ever remain pure.