Surah Al-Mu'minun 23:1
قَدْ أَفْلَحَ ٱلْمُؤْمِنُونَ
Certainly will the believers have succeeded:
Translation: Saheeh International
Tafsir
Indeed qad is for confirmation prosperous victorious are the believers
Excerpt from Tafsir al-Jalalayn, commentary on 23:1, via Quran.com. The reader has the full commentary and 9 more tafsirs.