Sahih Bukhari Volume 8, Book 78, Hadith 6167

حَدَّثَنَا سُلَيْمَانُ بْنُ عَبْدِ الرَّحْمَنِ، حَدَّثَنَا الْوَلِيدُ، حَدَّثَنَا أَبُو عَمْرٍو الأَوْزَاعِيُّ، قَالَ حَدَّثَنِي ابْنُ شِهَابٍ الزُّهْرِيُّ، عَنْ عَطَاءِ بْنِ يَزِيدَ اللَّيْثِيِّ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ ـ رضى الله عنه أَنَّ أَعْرَابِيًّا قَالَ يَا رَسُولَ اللَّهِ أَخْبِرْنِي عَنِ الْهِجْرَةِ‏.‏ فَقَالَ ‏"‏ وَيْحَكَ إِنَّ شَأْنَ الْهِجْرَةِ شَدِيدٌ، فَهَلْ لَكَ مِنْ إِبِلٍ ‏"‏‏.‏ قَالَ نَعَمْ‏.‏ قَالَ ‏"‏ فَهَلْ تُؤَدِّي صَدَقَتَهَا ‏"‏‏.‏ قَالَ نَعَمْ‏.‏ قَالَ ‏"‏ فَاعْمَلْ مِنْ وَرَاءِ الْبِحَارِ، فَإِنَّ اللَّهَ لَنْ يَتِرَكَ مِنْ عَمَلِكَ شَيْئًا ‏"‏‏.‏

Narrated By Abu Sa'id Al-Khudri : A bedouin said, "O Allah's Apostle! Inform me about the emigration." The Prophet said, "Waihaka (May Allah be merciful to you)! The question of emigration is a difficult one. Have you got some camels?" The bedouin said, "Yes." The Prophet said, "Do you pay their Zakat?" He said, "Yes." The Prophet said, "Go on doing like this from beyond the seas, for Allah will not let your deeds go in vain."