Al-Mustawrid reported: The Prophet, peace and blessings be upon him, said, “Whoever eats a meal at the expense of a Muslim, then Allah will feed him a like amount of Hellfire. Whoever clothes himself at the expense of a Muslim, then Allah will clothe him with a like amount of Hellfire. Whoever gains a position at the expense of a man and for the sake of showing off, then Allah will place him among the show-offs on the Day of Resurrection.”
Source: Al-Adab Al-Mufrad 240
Grade: Hasan (fair) according to Al-Bukhari
عَنِ الْمُسْتَوْرِدِ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ مَنْ أَكَلَ بِمُسْلِمٍ أُكْلَةً فَإِنَّ اللَّهَ يُطْعِمُهُ مِثْلَهَا مِنْ جَهَنَّمَ وَمَنْ كُسِيَ بِرَجُلٍ مُسْلِمٍ فَإِنَّ اللَّهَ عَزَّ وَجَلَّ يَكْسُوهُ مِنْ جَهَنَّمَ وَمَنْ قَامَ بِرَجُلٍ مَقَامَ رِيَاءٍ وَسُمْعَةٍ فَإِنَّ اللَّهَ يَقُومُ بِهِ مَقَامَ رِيَاءٍ وَسُمْعَةٍ يَوْمَ الْقِيَامَةِ
240 الأدب المفرد البخاري بَابُ الْمُسْلِمُ مَرْآةُ أَخِيهِ