[Machine] We were with the Messenger of Allah ﷺ on a journey when the Messenger of Allah ﷺ fell behind and we caught up with him and the prayer had become difficult for us. Then a caller called out from the Messenger of Allah ﷺ, "Woe to the stragglers from the Fire!"  

كُنَّا مَعَ رَسُولِ اللهِ ﷺ فِي سَفَرٍ قَالَ فَتَخَلَّفَ رَسُولُ اللهِ ﷺ وَأَدْرَكَنَا وَقَدْ رَهِقَتْنَا الصَّلَاةُ «فَنَادَى مُنَادِي رَسُولِ اللهِ ﷺ وَيْلٌ لِلْأَعْقَابِ مِنَ النَّارِ»  

Once the Prophet ﷺ remained behind us in a journey. He joined us while we were performing ablution for the prayer which was over-due. We were just passing wet hands over our feet (and not washing them properly) so the Prophet ﷺ addressed us in a loud voice and said twice or thrice: "Save your heels from the fire." (Using translation from Bukhārī 60)  

تَخَلَّفَ عَنَّا رَسُولُ اللهِ ﷺ فِي سَفْرَةٍ سَافَرْنَاهَا فَأَدْرَكَنَا وَقَدْ رَهِقَتْنَا صَلَاةُ الْعَصْرِ وَنَحْنُ نَتَوَضَّأُ فَجَعَلْنَا نَمْسَحُ عَلَى أَرْجُلِنَا فَنَادَى بِأَعْلَى صَوْتِهِ «وَيْلٌ لِلْعَرَاقِيبِ مِنَ النَّارِ» مَرَّتَيْنِ أَوْ ثَلَاثًا