ENOfficial
It was narrated from Abdullah that: He saw a man praying with his feet together. He said: "He is not following the Sunnah. If he were to shift his weight from one to the other I would like that better."
Source: sunnah.com
Other translations
Arabic
أَخْبَرَنَا إِسْمَاعِيلُ بْنُ مَسْعُودٍ، قَالَ حَدَّثَنَا خَالِدٌ، عَنْ شُعْبَةَ، قَالَ أَخْبَرَنِي مَيْسَرَةُ بْنُ حَبِيبٍ، قَالَ سَمِعْتُ الْمِنْهَالَ بْنَ عَمْرٍو، يُحَدِّثُ عَنْ أَبِي عُبَيْدَةَ، عَنْ عَبْدِ اللَّهِ، أَنَّهُ رَأَى رَجُلاً يُصَلِّي قَدْ صَفَّ بَيْنَ قَدَمَيْهِ فَقَالَ أَخْطَأَ السُّنَّةَ وَلَوْ رَاوَحَ بَيْنَهُمَا كَانَ أَعْجَبَ إِلَىَّ .
sunnah.com