(37) باب اقْرَءُوا الْقُرْآنَ مَا ائْتَلَفَتْ قُلُوبُكُمْ
Narrated `Abdullah:
That he heard a man reciting a Quranic Verse which he had heard the Prophet (ﷺ) reciting in a different way. So he took that man to the Prophet (and told him the story). The Prophet (ﷺ) said, "Both of you are reciting in a correct way, so carry on reciting." The Prophet (ﷺ) further added, "The nations which were before you were destroyed (by Allah) because they differed."
Reference: Sahih al-Bukhari 5062
In-book reference: Book 66, Hadith 87
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 6, Book 61, Hadith 582