(67) باب جَوَازِ الاِسْتِسْرَارِ لِلْخَائِفِ
Hudhaifa reported:
We were in the company of the Messenger of Allah (ﷺ) when he said. Count for me those who profess al-Islam. We said: Messenger of Allah, do you entertain any fear concerning us and we are (at this time) between six hundred and seven hundred (in strength). He (the Holy Prophet) remarked: You don't perceive; you may be put to some trial, He (the narrator) said: We actually suffered trial so much so that some of our men were constrained to offer their prayers in concealment.
Reference: Sahih Muslim 149
In-book reference: Book 1, Hadith 284
USC-MSA web (English) reference(deprecated numbering scheme): Book 1, Hadith 275