مِشْكَاةُ الْمَصَابِيحِ
Mishkat al-Masabih 686
Prayer
Chapter - Section 1
وَعَنْ أَبِي هُرَيْرَةَ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «إِذَا أُقِيمَت الصَّلَاة فَلَا تأتوها تَسْعَوْنَ وَأْتُوهَا تَمْشُونَ وَعَلَيْكُمُ السَّكِينَةُ فَمَا أَدْرَكْتُمْ فَصَلُّوا وَمَا فاتكم فَأتمُّوا» وَفِي رِوَايَةٍ لِمُسْلِمٍ: «فَإِنَّ أَحَدَكُمْ إِذَا كَانَ يَعْمِدُ إِلَى الصَّلَاةِ فَهُوَ فِي صَلَاةٍ»
Abu Huraira reported God’s Messenger as saying, "When the iqama has been pronounced for prayer, do not go running to it, but go walking in tranquility, and pray what you are in time for and complete what you have missed.” (Bukhari and Muslim.) A version by Muslim has, "for when one of you is making for prayer he is engaged in prayer.”
Mishkat al-Masabih, 686