Abu Hurairah reported,

The call to begin prayer was made, so we stood up and straightened the rows before the Messenger of Allah ﷺ came out to us. The Messenger of Allah ﷺ came forward, and when he stood at his place of prayer, before he pronounced the opening takbir, he remembered something. He turned away and said to us, "Stay where you are."We remained standing, waiting for him, until he came back out to us having performed a full bath, with water dripping from his head. He then pronounced the takbir and led us in prayer.

Azami 1917

Sahih

عن أبي هريرة قال

أقيمت الصلاة، فقمنا، فعدلنا الصفوف قبل أن يخرج إلينا رسول الله ﷺ، فأتى رسول الله ﷺ حتى إذا قام في مصلاه قبل أن يكبر ذكر، فانصرف وقال لنا: مكانكم فلم نزل قياما ننتظره حتى خرج إلينا وقد اغتسل، ينظف رأسه ماء، فكبر فصلى بنا.

الأعظمي 1917صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Prayer
Chapter
Adhan
Section
Muezzin calls the iqamah before the imam comes out
Numbering
Jami al-Kamil 1917 (2nd edition)
Azami 1917