Mujahid reported,

Ibn Umar witnessed the Conquest when he was twenty years old. He had with him a stubborn horse and a heavy spear. Ibn Umar went off to gather fodder for his horse, and the Messenger of Allah ﷺ said, "Abdullah! Abdullah!"

Ahmad 4600

Sahih

حدثنا سفيان عن ابن أبي نجيح

عن مجاهد قال

شهد ابن عمر الفتح وهو ابن عشرين سنة ومعه فرس حرون ورمح ثقيل فذهب ابن عمر يختلي لفرسه فقال رسول الله ﷺ إن عبد الله إن عبد الله

أحمد 4600صحيح
Contents
Reference
Commentary
Ayat
Collection
Musnad Ahmad
Book
Abdullah bin Umar
Numbering
Darussalam 4600
Ahmad 4600