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.
bayhaqi:2403[Chain 1] Abū Saʿd al-Zāhid > Abū Isḥāq Ibrāhīm b. Muḥammad b. Yaḥyá > Muḥammad b. Sulaymān b. Fāris > Aḥmad b. al-Walīd > ʿAtīq b. Yaʿqūb al-Zubayrī [Chain 2] Abū Ḥāzim al-Ḥāfiẓ > Abū Aḥmad al-Ḥāfiẓ > Abū Jaʿfar Muḥammad b. ʿAbd al-Raḥman al-Ḍabbī > Aḥmad b. Yaḥyá al-Ḥulwānī > ʿAtīq b. Yaʿqūb al-Zubayrī > ʿAbd al-Raḥman b. ʿAbdullāh b. ʿUmar from his father from his uncle ʿUbaydullāh / Ibn ʿUmar > Nāfiʿ > Ibn ʿUmar

[Machine] The Messenger of Allah ﷺ used to start his prayer with "Bismillah al-Rahman al-Rahim" (In the name of Allah, the Most Gracious, the Most Merciful) [Surah Al-Fatiha 1]. In the narration of Al-Zahid, it is mentioned that he recited it and added that Abdullah ibn Umar used to also recite "Bismillah al-Rahman al-Rahim" in the opening of the prayer, both in the beginning of Surah Al-Fatiha and the following surah. And the correct opinion is that it should be stopped at that.  

البيهقي:٢٤٠٣حَدَّثَنَا أَبُو سَعْدٍ الزَّاهِدُ ثنا أَبُو إِسْحَاقَ إِبْرَاهِيمُ بْنُ مُحَمَّدِ بْنِ يَحْيَى ثنا مُحَمَّدُ بْنُ سُلَيْمَانَ بْنِ فَارِسٍ ثنا أَحْمَدُ بْنُ الْوَلِيدِ ثنا عَتِيقُ بْنُ يَعْقُوبَ الزُّبَيْرِيُّ ح وَأَخْبَرَنَا أَبُو حَازِمٍ الْحَافِظُ أَخْبَرَنِي أَبُو أَحْمَدَ الْحَافِظُ أَخْبَرَنِي أَبُو جَعْفَرٍ مُحَمَّدُ بْنُ عَبْدِ الرَّحْمَنِ الضَّبِّيُّ ثنا أَحْمَدُ بْنُ يَحْيَى الْحُلْوَانِيُّ ثنا عَتِيقُ بْنُ يَعْقُوبَ الزُّبَيْرِيُّ حَدَّثَنِي عَبْدُ الرَّحْمَنِ بْنُ عَبْدِ اللهِ بْنِ عُمَرَ عَنْ أَبِيهِ وَعَنْ عَمِّهِ عُبَيْدِ اللهِ يَعْنِي ابْنَ عُمَرَ عَنْ نَافِعٍ عَنِ ابْنِ عُمَرَ

أَنَّ رَسُولَ اللهِ ﷺ كَانَ إِذَا افْتَتَحَ الصَّلَاةَ يَبْدَأُ بِ {بِسْمِ اللهِ الرَّحْمَنِ الرَّحِيمِ} [الفاتحة 1] وَفِي رِوَايَةِ الزَّاهِدِ يَقْرَأُ وَزَادَ فِي رِوَايَتِهِ وَإِنَّ عَبْدَ اللهِ بْنَ عُمَرَ كَانَ إِذَا افْتَتَحَ الصَّلَاةَ يَقْرَأُ بِسْمِ اللهِ الرَّحْمَنِ الرَّحِيمِ فِي أُمِّ الْكِتَابِ وَفِي السُّورَةِ الَّتِي تَلِيهَا وَالصَّوَابُ مَوْقُوفٌ كَذَلِكَ  

رَوَاهُ أَيُّوبُ وَابْنُ جُرَيْجٍ وَغَيْرُهُمَا عَنْ نَافِعٍ