Narrated Abu Hurairah (RA):

Allah's Messenger (ﷺ) forbade keeping one's hands on one's waist while praying. [Agreed upon]. The wording is that of Muslim's. And it's meaning is to put (one's) hands on his waist.

عَنْ أَبِي هُرَيْرَةَ ‏- رضى الله عنه ‏- قَالَ : { نَهَى رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-أَنْ يُصَلِّيَ اَلرَّجُلُ مُخْتَصِرًا } مُتَّفَقٌ عَلَيْهِ , وَاللَّفْظُ لِمُسْلِمٍ .‏ [1]‏ وَمَعْنَاهُ : أَنْ يَجْعَلَ يَدَهُ عَلَى خَاصِرَتِهِ [2]‏