Surah Fussilat 41:33
وَمَنْ أَحْسَنُ قَوْلًا مِّمَّن دَعَآ إِلَى ٱللَّهِ وَعَمِلَ صَٰلِحًا وَقَالَ إِنَّنِى مِنَ ٱلْمُسْلِمِينَ ٣٣
EnglishSahih International
And who is better in speech than one who invites to Allah and does righteousness and says, "Indeed, I am of the Muslims."