I heard Usama bin Sharik saying: I came to the Prophet ﷺ, and his companions we as if they birds were perched on their heads (i.e. they were still and attentive).
سَمِعْتُ أُسَامَةَ بْنَ شَرِيكٍ يَقُولُ «أَتَيْتُ رَسُولَ اللهِ ﷺ فَإِذَا أَصْحَابُهُ عِنْدَهُ كَأَنَّ عَلَى رُءُوسِهِمُ الطَّيْرُ»