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Narrated Abu Sa`id Al-Khudri:

A bedouin said, "O Allah's Messenger (ﷺ)! Inform me about the emigration." The Prophet (ﷺ) 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 (ﷺ) 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."

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 ‏"‏‏.‏
Reference : Sahih al-Bukhari 6165
In-book reference : Book 78, Hadith 191
USC-MSA web (English) reference : Vol. 8, Book 73, Hadith 186
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