(390) بَابُ الضَّرْبِ عَلَى اللَّحْنِ
'Abdu'r-Rahman ibn 'Ajlan said, "'Umar ibn al-Khattab, may Allahbe pleased with him, passed by two men who were shooting. One man saidto another, 'Do hit it (using the letter seen instead of saad).''Umar observed, 'A bad grammatical mistake is worse than a bad shot.'"
Reference: Al-Adab Al-Mufrad 881
In-book reference: Book 37, Hadith 7
English translation: Book 37, Hadith 881