Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
quran:3:16 –

Those who say, "Our Lord, indeed we have believed, so forgive us our sins and protect us from the punishment of the Fire,"  

Those (alladhīna is either an adjectival qualification of, or a substitution for, the previous alladhīna) who say: “O, Our Lord, we believe, in You and in Your Prophet; so forgive us our sins, and guard us from the chastisement of the Fire”.
القرآن:٣:١٦ –

الَّذِينَ يَقُولُونَ رَبَّنَا إِنَّنَا آمَنَّا فَاغْفِرْ لَنَا ذُنُوبَنَا وَقِنَا عَذَابَ النَّارِ  

{الذين} نعت أو بدل من الذين قبله {يقولون} يا {ربَّنا إننا آمنا} صدَّقنا بك وبرسولك {فاغفر لنا ذنوبنا وقنا عذاب النار}.