Full Sharh — Mishkat al-Masabih 3632
وَعَن سلمانَ الفارسيِّ قَالَ: سَمِعْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ: «رِبَاطُ يَوْمٍ وَلَيْلَةٍ فِي سَبِيلِ اللَّهِ خَيْرٌ مِنْ صِيَامِ شَهْرٍ وَقِيَامِهِ وَإِنْ مَاتَ جَرَى عَلَيْهِ عَمَلُهُ الَّذِي كَانَ يَعْمَلُهُ وَأُجْرِيَ عَلَيْهِ رِزْقُهُ وَأَمِنَ الْفَتَّانَ» . رَوَاهُ مُسْلِمٌ
English Translation
Salman al-Fairisi told that he heard God’s Messenger say, “Being stationed for a day and a night on the frontier in God’s path is better than fasting a month and spending its nights in prayer. If one dies he will be rewarded for the deeds he was doing, he will be given his provision, and will be safe from him who tests him.”* * Al-fattan. There is some doubt as to the reference here. It may be the devil, this name being used because he tempts people to sin; or it may mean the one who examines men in the grave. Munkar and Nakir are called fattana'l-qabr, the two who test men in the grave. Muslim transmitted it.
Source
Mishkat al-Masabih(مشكاة المصابيح)
Jihad
Hadith Number
3632