Worst companions require formality
Nahj al-Balāgha|Volume 1|Book 3|Chapter 479
قال السيد الرضي: لأن التكليف مستلزمٌ للمشقة، وهو شرٌ لازمٌ عن الأخ المتَكلّفِ له، فهو شرُّ الإخوان.
as-Sayyid ar-Raḍī says: This is because formality is inseparable from hardship and it is an evil that is caused by a comrade for whom formality is observed. Consequently, he is the worst of all comrades.