Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
tabarani:13523[Chain 1] Ibrāhīm b. Aḥmad al-Wakīʿī from my father [Chain 2] Aḥmad b. Shuʿayb Abū ʿAbd al-Raḥman al-Nasāʾī > Muḥammad b. Rāfiʿ al-Naysābūrī > Yaḥyá b. Ādam > Mufaḍḍal b. Muhalhal > Manṣūr > Mujāhid > Ibn ʿUmar

[Machine] The Messenger of Allah performed Umrah four times, one of them in the month of Rajab.  

الطبراني:١٣٥٢٣حَدَّثَنَا إِبْرَاهِيمُ بْنُ أَحْمَدَ الْوَكِيعِيُّ ثنا أَبِي ح وَحَدَّثَنَا أَحْمَدُ بْنُ شُعَيْبٍ أَبُو عَبْدِ الرَّحْمَنِ النَّسَائِيُّ أنا مُحَمَّدُ بْنُ رَافِعٍ النَّيْسَابُورِيُّ قَالَا ثنا يَحْيَى بْنُ آدَمَ عَنْ مُفَضَّلِ بْنِ مُهَلْهَلٍ عَنْ مَنْصُورٍ عَنْ مُجَاهِدٍ عَنِ ابْنِ عُمَرَ قَالَ

«اعْتَمَرَ رَسُولُ اللهِ ﷺ أَرْبَعَ عُمَرٍ إِحْدَاهُنَّ فِي رَجَبٍ»  


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Collected by Tirmidhī
tirmidhi:937Aḥmad b. Manīʿ > al-Ḥasan b. Mūsá > Shaybān > Manṣūr > Mujāhid > Ibn ʿUmar

"The Prophet performed Umrah four times, one of them was during Rajab."  

Abū ʿĪsá said that this Ḥadīth is Ḥasan-Ṣaḥīḥ-Gharīb.
الترمذي:٩٣٧حَدَّثَنَا أَحْمَدُ بْنُ مَنِيعٍ حَدَّثَنَا الْحَسَنُ بْنُ مُوسَى حَدَّثَنَا شَيْبَانُ عَنْ مَنْصُورٍ عَنْ مُجَاهِدٍ عَنِ ابْنِ عُمَرَ

أَنَّ النَّبِيَّ ﷺ اعْتَمَرَ أَرْبَعًا إِحْدَاهُنَّ فِي رَجَبٍ  

قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ غَرِيبٌ