in the question.

What did Ibn 'Umar remember when Muawiya asked if anyone wanted to say something about the Caliphate, that motivated him to remain silent?
 Narrated `Ikrima bin Khalid:                     Ibn `Umar said, "I went to Hafsa while water was dribbling from her twined braids. I said, 'The condition of the people is as you see, and no authority has been given to me.' Hafsa said, (to me), 'Go to them, and as they (i.e. the people) are waiting for you, and I am afraid your absence from them will produce division amongst them.' " So Hafsa did not leave Ibn `Umar till we went to them. When the people differed. Muawiya addressed the people saying, "'If anybody wants to say anything in this matter of the Caliphate, he should show up and not conceal himself, for we are more rightful to be a Caliph than he and his father." On that, Habib bin Masalama said (to Ibn `Umar), "Why don't you reply to him (i.e. Muawiya)?" `Abdullah bin `Umar said, "I untied my garment that was going round my back and legs while I was sitting and was about to say, 'He who fought against you and against your father for the sake of Islam, is more rightful to be a Caliph,' but I was afraid that my statement might produce differences amongst the people and cause bloodshed, and my statement might be interpreted not as I intended. (So I kept quiet) remembering what Allah has prepared in the Gardens of Paradise (for those who are patient and prefer the Hereafter to this worldly life)." Habib said, "You did what kept you safe and secure (i.e. you were wise in doing so).