Abu Ayyub al-Ansari (Allah be pleased with him) reported Allah's Messenger (ﷺ) as saying
He who observed the fast of Ramadan and then followed it with six (fasts) of Shawwal. it would be as if he fasted perpetually.
Abu Ayyub al-Ansari reported (through another chain of transmitters)
I heard Allah's Messenger (ﷺ) saying like this.
Abu Ayyub reported a hadith like this (through another chain of transmitters).