Sayyiduna Jabir (may Allah be pleased with him) narrates: It was asked: O Messenger of Allah! How will you recognise that person, a member of your Ummah whom you (peace and blessings be upon him) have not seen? The Prophet (peace and blessings be upon him) said: By the brightness. (The narrator states:) I think the report also contains these words: they will be radiant because of the traces of ablution.
Imam al-Bazzar recorded this report, and its chain is hasan (good).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الطهارة / 1142