Question:
What is the authenticity of the narration “Lā tansanā yā akhī min duʿāʾik” (“Do not forget us, my brother, in your supplications”) reported by Imām Abū Dāwūd and Imām al-Tirmidhī?
Source: Fatāwā Amunpuri by Shaykh Ghulam Mustafa Zaheer Amunpuri
Answer:
The chain of this narration is weak (ḍaʿīf).
The narration is reported from ʿUmar ibn al-Khaṭṭāb رضي الله عنه, who said:
استأذنت النبى صلى الله عليه وسلم فى العمرة، فأذن لي، وقال: لا تنسنا يا أخي من دعائك
“I sought permission from the Prophet ﷺ to perform ʿUmrah. He permitted me and said: ‘Do not forget us, my brother, in your supplications.’”
(Sunan Abī Dāwūd: 1498; Sunan al-Tirmidhī: 3562; Sunan Ibn Mājah: 2894)
Reasons for Weakness in the Chain:
❀ ʿĀṣim ibn ʿUbaydullāh – weak due to poor memory.
- Imām Ibn Ḥibbān رحمه الله:
كان سيئ الحفظ كثير الوهم فاحش الخطأ فترك من أجل كثرة خطئه
“He was poor in memory, committed many mistakes, and was grossly erroneous. He was abandoned due to the abundance of his errors.”
(Kitāb al-Majrūḥīn, 2/127)
❀ Asbaṭ ibn Muḥammad – problematic when narrating from Sufyān al-Thawrī.
- Imām Yaḥyā ibn Maʿīn رحمه الله:
كان يخطئ عن سفيان
“He made mistakes when narrating from Sufyān.”
(Tārīkh al-Dūrī, 4/49)
❀ Additionally, there is ʿanʿanah of Sufyān al-Thawrī, further weakening the chain.

The narration “Lā tansanā yā akhī min duʿāʾik” is weak in sanad due to the poor memory of ʿĀṣim ibn ʿUbaydullāh, errors of Asbaṭ ibn Muḥammad in narrations from Sufyān al-Thawrī, and the issue of ʿanʿanah.