It is narrated from al-Hasan (may Allah have mercy on him) that Sayyiduna Abu Bakrah (may Allah be pleased with him) entered the mosque while the Prophet (peace and blessings be upon him) had already gone into bowing. He too bowed before joining the row. The Prophet (peace and blessings be upon him) said (after the prayer): "May Allah Almighty increase your eagerness (for prayer). Do not do it like this again."
Imam al-Shafi'i (may Allah have mercy on him) said: His (peace and blessings be upon him) words 'Do not do it again' are like his saying 'Do not come to the prayer running.' That is: it is not required of you to bow until you reach your place in the row, because there is hardship in that, just as it is not required of you to run when you hear the iqamah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2584
Hadith Gradingمحدثین:صحيح
Hadith Takhrij«صحيح۔ امام بخاريa ني موسيٰ بن اسماعيل عن همام روايت كي هي۔ اخرجه مالك في الموطا 285»