Sahih Bukhari Volume 4, Book 56, Hadith 2797

قَالَ: وَسَمِعْتُ أَنَسَ بْنَ مَالِكٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم ‏"‏ لَرَوْحَةٌ فِي سَبِيلِ اللَّهِ أَوْ غَدْوَةٌ خَيْرٌ مِنَ الدُّنْيَا وَمَا فِيهَا، وَلَقَابُ قَوْسِ أَحَدِكُمْ مِنَ الْجَنَّةِ أَوْ مَوْضِعُ قِيدٍ ـ يَعْنِي سَوْطَهُ ـ خَيْرٌ مِنَ الدُّنْيَا وَمَا فِيهَا، وَلَوْ أَنَّ امْرَأَةً مِنْ أَهْلِ الْجَنَّةِ اطَّلَعَتْ إِلَى أَهْلِ الأَرْضِ لأَضَاءَتْ مَا بَيْنَهُمَا وَلَمَلأَتْهُ رِيحًا، وَلَنَصِيفُهَا عَلَى رَأْسِهَا خَيْرٌ مِنَ الدُّنْيَا وَمَا فِيهَا ‏"‏‏

Narrated Anas: The Prophet said, "A single endeavour (of fighting) in Allah's Cause in the afternoon or in the forenoon is better than all the world and whatever is in it. A place in Paradise as small as the bow or lash of one of you is better than all the world and whatever is in it. And if a houri from Paradise appeared to the people of the earth, she would fill the space between Heaven and the Earth with light and pleasant scent and her head cover is better than the world and whatever is in it."