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.
bukhari:724Muʿādh b. Asad > al-Faḍl b. Mūsá > Saʿīd b. ʿUbayd al-Ṭāʾī > Bushayr b. Yasār al-Anṣārī > Anas b. Mālik

I arrived at Medina and was asked whether I found any change since the days of Messenger of Allah ﷺ. I said, "I have not found any change except that you do not stand in alignment in your prayers."  

البخاري:٧٢٤حَدَّثَنَا مُعَاذُ بْنُ أَسَدٍ قَالَ أَخْبَرَنَا الْفَضْلُ بْنُ مُوسَى قَالَ أَخْبَرَنَا سَعِيدُ بْنُ عُبَيْدٍ الطَّائِيُّ عَنْ بُشَيْرِ بْنِ يَسَارٍ الأَنْصَارِيِّ عَنْ أَنَسِ بْنِ مَالِكٍ

أَنَّهُ قَدِمَ الْمَدِينَةَ فَقِيلَ لَهُ مَا أَنْكَرْتَ مِنَّا مُنْذُ يَوْمِ عَهِدْتَ رَسُولَ اللَّهِ ﷺ قَالَ مَا أَنْكَرْتُ شَيْئًا إِلاَّ أَنَّكُمْ لاَ تُقِيمُونَ الصُّفُوفَ وَقَالَ عُقْبَةُ بْنُ عُبَيْدٍ عَنْ بُشَيْرِ بْنِ يَسَارٍ قَدِمَ عَلَيْنَا أَنَسُ بْنُ مَالِكٍ الْمَدِينَةَ بِهَذَا