Mishkat al-Masabih 798

The people were ordered to place the right hand on the left forearm in the prayer. Abu Hazim said, "I knew that the order was from the Prophet (ﷺ) ."

كَانَ النَّاسُ يُؤْمَرُونَ أَنْ يَضَعَ الرَّجُلُ الْيَدَ الْيُمْنَى عَلَى ذِرَاعِهِ الْيُسْرَى فِي الصَّلاَةِ‏.‏

Narrated by Sahl ibn Sa‘d

Yahya related to me from Malik from Abu Hazim ibn Dinar that Sahl ibn Sad said, "People used to be ordered to place their right hands on their left forearms in the prayer." Abu Hazim added, "I know for sure that Sahl traces that back to the Prophet, may Allah bless him and grant him peace."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ أَبِي حَازِمِ بْنِ دِينَارٍ، عَنْ سَهْلِ بْنِ سَعْدٍ، أَنَّهُ قَالَ كَانَ النَّاسُ يُؤْمَرُونَ أَنْ يَضَعَ الرَّجُلُ الْيَدَ الْيُمْنَى عَلَى ذِرَاعِهِ الْيُسْرَى فِي الصَّلاَةِ ‏.‏ قَالَ…