Hadith: O Allah, I do love him. So love him and love whoever loves him

عن أبي هريرة رضي الله عنه قال: كنتُ مع رسول الله صلى الله عليه وسلم في سوق من أسواق المدينة، فانصرف فانصرفتُ، فقال: «أين لُكَعُ -ثلاثا- ادعُ الحسن بن علي». فقام الحسن بن علي يمشي وفي عنقه السِّخَاب، فقال النبي صلى الله عليه وسلم بيده هكذا، فقال الحسن بيده هكذا، فالتزمه فقال: «اللهم إني أُحبه فأَحبَّه، وأَحبَّ من يحبه». وقال أبو هريرة: فما كان أحد أحب إليَّ من الحسن بن علي، بعد ما قال رسول الله صلى الله عليه وسلم ما قال.
[صحيح] - [متفق عليه]

Abu Hurayrah (may Allah be pleased with him) reported: I was accompanying the Messenger of Allah (may Allah's peace and blessings be upon him) in one of the markets of Madīnah. He left and so did I. He said: "Where is Luka‘?" He repeated this three times and then said: "Call Al-Hasan ibn ‘Ali." Al-Hasan got up and walked [towards him] and he had a necklace round his neck. The Prophet (may Allah's peace and blessings be upon him) had his hand like this and Al-Hasan’s hand was the same and he hugged him and said: "O Allah, I do love him. So love him and love whoever loves him." Abu Hurayrah said: "There is none more beloved to me than Al-Hasan ibn ‘Ali." He said that after he heard the Messenger of Allah (may Allah's peace and blessings be upon him) had said what he said about him.
[Authentic hadith] - [Narrated by Bukhari & Muslim]

Explanation

Abu Hurayrah (may Allah be pleased with him) was with the Messenger of Allah (may Allah's peace and blessings be upon him) in one of the markets of Madīnah. The Messenger of Allah (may Allah's peace and blessings be upon him) left the market and so did Abu Hurayrah. he went to the house of Fātimah, (may Allah be pleased with her) and asked about Al-Hasan,(may Allah be pleased with him) asking: "Where is Luka‘?" He meant: where is the little child? He then said: "Call him for me." Al-Hasan got up and walked towards the Prophet wearing a necklace around his neck. The Prophet (may Allah's peace and blessings be upon him) stretched his hand out to hug Al-Hasan and he did the same thing. They hugged each other. The Prophet (may Allah's peace and blessings be upon him) said: "O Allah, I do love Al-Hasan. So love him and love whoever loves him." Abu Hurayrah commented: "There was none more beloved to me than Al-Hasan ibn ‘Ali. He said that after he heard the Messenger of Allah (may Allah's peace and blessings be upon him) had said what he said about him.