The Peak of Eloquence · Hadith 1412 (#Passage #221)

وَقَدْ عَرَفْتُ أَنَّ مُعَاويَةَ كَتَبَ إِلَيْكَ يَسْتَزِلُّ لُبَّكَ، وَيَسْتَفِلُّ غَرْبَكَ، فاحْذَرْهُ، فَإِنَّمَا هُوَ الشَّيْطَانُ يَأْتِي الْمَرْءَ مِنْ بَيْنِ يَدَيْهِ وَمِنْ خَلْفِهِ، وَعَنْ يَمينِهِ وَعَنْ شِمَالِهِ، لِيَقْتَحِمَ غَفْلَتَهُ، وَيَسْتَلِبَ غِرَّتَهُ.

I have learnt that Mu‘āwiyah has written to you to deceive your wit and blunt your sharpness. You should be on guard against him because he is the Satan who approaches a believer from the front and from the back, from the right and from the left, to catch him suddenly in the hour of his carelessness and overcome his intelligence.

Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).