KNOW THAT THE hadiths on this subject are innumerable, and there is unanimity about this matter. Among the best evidence in proof of it is that which we relate in the books of Abū Dāwūd and at-Tirmidhī. ‘Umar ibn al-Khaṭṭāb
narrated: “I asked the Prophet
for permission to perform ‘Umrah. He granted me permission and said: ‘Do not forget us, my brother, in your du‘ā’.’ He said something that was more pleasing to me than owning the world.”
According to another report he said: “Let us share in your du‘ā’, my brother.” [1].According to at-Tirmidhī, this is a ḥasan ṣaḥīḥ hadith; and we have already cited it among the adhkār for travellers.
References
[1] Abū Dāwūd (1498) and at-Tirmidhī (3557).