Bulugh al-Maram, Book 6, Hadith 3 (In-Book)

Jabir bin 'Abdullah (RAA) narrated, A Bedouin came to the Prophet and said, ‘O Messenger of Allah! Tell me about 'Umrah! Is it compulsory? He replied, “No (it is not compulsory), but it is better for you to perform it.” Related by Ahmad and at-Tirmidhi. Scholars are of the opinion that it is Mawquf.

وَعَنْ جَابِرِ بْنِ عَبْدِ اَللَّهِ رَضِيَ اَللَّهُ عَنْهُمَا قَالَ: { أَتَى اَلنَّبِيَّ ‏- صلى الله عليه وسلم ‏-أَعْرَابِيٌّ.‏ فَقَالَ: يَا رَسُولَ اَللَّهِ! أَخْبِرْنِي عَنْ اَلْعُمْرَةِ, أَوَاجِبَةٌ هِيَ? فَقَالَ: " لَا.‏ وَأَنْ تَعْتَمِرَ خَيْرٌ لَكَ " } رَوَاهُ أَحْمَدُ, وَاَلتِّرْمِذِيُّ, وَالرَّاجِحُ وَقْفُهُ 1‏.‏ ‏1 ‏- ضعيف مرفوعا وموقوفا.‏ رواه أحمد ( 3 / 316 )‏، والترمذي ( 931 )‏.‏

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also referenced under: Book 6, Hadith 730 (English)