Ibn Majah

Commentary: (1) (مُتَكِّئاً)
The meaning of this is to sit while eating with one's back supported by something. Some scholars have explained it as sitting with one hand resting on the ground or sitting cross-legged (with both legs folded under oneself). Since sitting with support or placing one's hand on the ground while eating is the manner of the arrogant, and sitting cross-legged is the way of a person who is accustomed to eating excessively and is gluttonous, therefore the Prophet sallallahu alayhi wa sallam refrained from this.

(2)
When one person walks ahead and others walk behind him, this demonstrates the arrogance of the one in front, as he considers himself superior to others and does not wish for others to walk alongside him. Moreover, this entails the humiliation of those walking behind, as they, in effect, consider themselves inferior to him.

(3)
That thing cannot be considered respectful which the Messenger of Allah sallallahu alayhi wa sallam has disliked.

(4)
Among some people, it is customary that when a spiritual guide (pir) or elder is sitting on a cot, they do not sit on the cot with him but rather sit on the ground. This too is a very wrong custom, because it contains even more humiliation than walking behind someone.