Hadith: May Allah increase your keenness, but do not do that again

عن الحسن، أن أبا بَكْرَة جاء ورسول الله راكع، فركع دون الصَّف ثم مَشَى إلى الصَّف فلما قَضَى النبي صلى الله عليه وسلم صلاته، قال: «أيُّكم الذي ركع دون الصَّف ثم مَشَى إلى الصَّف؟» فقال أبو بَكْرَة: أنا، فقال النبي صلى الله عليه وسلم : «زادَك الله حِرْصَا ولا تَعُد».
[صحيح] - [رواه أبو داود وأحمد، وأصله عند البخاري]

Al-Hasan (may Allah be pleased with him) reported: Abu Bakrah came while the Messenger of Allah (may Allah’s peace and blessings be upon him) was bowing, so he bowed before reaching the row and then walked to it. When the Prophet (may Allah's peace and blessings be upon him) finished the prayer, he said: "Which one of you bowed before reaching the row and then walked thereto?" Abu Bakrah replied: "It was me." The Prophet (may Allah's peace and blessings be upon him) said: "May Allah increase your keenness, but do not do that again."
Sahih/Authentic. - [Abu Dawood]

Explanation

Abu Bakrah (may Allah be pleased with him) entered the mosque and found the Prophet (may Allah's peace and blessings be upon him) and his Companions in the bowing position. So, he hastened to bow before reaching the row so as to catch up with this Rak‘ah. Then, he walked to the row while bowing until he joined it. Meanwhile, the Prophet (may Allah's peace and blessings be upon him) perceived there was some movement behind the row and that someone came hastily and bowed before reaching the row. It was a characteristic of the Prophet (may Allah's peace and blessings be upon him) that he could see what was behind him during prayer as he could see in front of him. Having finished the prayer, the Prophet (may Allah's peace and blessings be upon him) asked: Who bowed before reaching the row and then walked to it? Abu Bakrah said: "It was me." In other words, I am the one who did what you said: O Messenger of Allah, In response, the Prophet (may Allah's peace and blessings be upon him) said: May Allah increase your desire and enthusiasm for doing good. But, do not walk quickly again to catch up the Rak‘ah or bow before reaching the row. Indeed, fast walking contradicts calmness and tranquility, which are required in prayer. In another Hadīth, the Prophet (may Allah's peace and blessings be upon him) said: "There is no prayer for a person who prays alone behind the row." However, Abu Bakrah’s action does not fall under this ruling, for he only performed a small part of the prayer alone. This is similar to the case of a person who bows alone and is subsequently joined by someone else while still in this position, forming a row together. However, Abu Bakrah’s action is not permissible, given the Prophet’s order: "But do not do that again.”