Hadith: I was with Qatādah ibn Milhān when he was in the throes of death. A man passed in a distant place in the house, so I saw him in the face of Qatādah. Whenever I saw him [in the past], his face as if had oil on it

عن أبي العَلاء بن عُمير رضي الله عنه ، قال: كنتُ عند قَتادة بن مِلْحان حين حُضِر، فمرَّ رجل في أقْصى الدَّار، قال: فأبْصرْتُه في وجْهِ قتادة، قال: وكنتُ إذا رأيتُه كأنَّ على وجْهِه الدِّهان، قال: «وكان رسول الله صلى الله عليه وسلم مَسَح على وجْهِه».
[صحيح] - [رواه أحمد]

Abu al-‘Alā ibn ‘Umayr (may Allah be pleased with him) reported: I was with Qatādah ibn Milhān when he was in the throes of death. A man passed in a distant place in the house, so I saw him in the face of Qatādah. Whenever I saw him [in the past], his face as if had oil on it. The Messenger of Allah (may Allah's peace and blessings be upon him) had wiped over his face.
[Authentic hadith] - [Narrated by Ahmad]

Explanation

Abu al-‘Alā ibn ‘Umayr was in the presence of Qatādah ibn Milhān (may Allah be pleased with him) when death came upon him. A man passed in a distant place in the house, so Abu al-‘Alā saw him in the face of Qatādah, for his face was like a mirror. Whenever he saw him [in the past], his face was as if it was coated with oil, because it was clear, bright, and shiny. The Messenger of Allah (may Allah's peace and blessings be upon him) had wiped over the face of Qatādah. Hence, he earned such brightness and shininess because of the blessing of the Prophet wiping over his face.