Mishkat al-Masabih 3089
Abu Huraira reported God’s Messenger as saying, “There are three whom it is right for God to help:
the slave whose master has agreed to let him buy his freedom when he wishes to pay the sum, the one who marries desiring to live a chaste life, and the one who fights in God’s path." 

Tirmidhi, Nasa’i and Ibn Majah transmitted it.
عَنْ أَبِي هُرَيْرَةَ أَنَّ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: 
" ثَلَاثَةٌ حَقٌّ عَلَى اللَّهِ عَوْنُهُمْ: الْمُكَاتَبُ الَّذِي يُرِيدُ الْأَدَاءَ وَالنَّاكِحُ الَّذِي يُرِيدُ الْعَفَافَ وَالْمُجَاهِدُ فِي سَبِيلِ اللَّهِ ". رَوَاهُ التِّرْمِذِيّ وَالنَّسَائِيّ وَابْن مَاجَه