The Messenger of Allah ﷺ said, "The Quran was revealed in seven modes."
قال حدثنا عفان قال حدثنا حماد قال أخبرنا حميد عن أنس عن عبادة أن
قال رسول الله ﷺ أنزل القرآن على سبعة أحرف
Its isnad is sahih, its narrators are leading authorities, and it includes three companions. This hadith has appeared many times before. See 17747.