We said our prayer with the Messenger of Allah ﷺ and, while pronouncing salutations, we made gestures with our hands (indicating)" Peace be upon you, peace be upon you." The Messenger of Allah ﷺ looked towards us and said: Why is it that you make gestures with your hands like the tails of headstrong horses? When any one of you pro- nounces salutation (in prayer) he should only turn his face towards his companion and should not make a gesture with his hand. (Using translation from Muslim 431b)  

صَلَّيْتُ مَعَ رَسُولِ اللهِ ﷺ فَكُنَّا إِذَا سَلَّمْنَا قُلْنَا بِأَيْدِينَا السَّلَامُ عَلَيْكُمْ السَّلَامُ عَلَيْكُمْ قَالَ فَنَظَرَ إِلَيْنَا رَسُولُ اللهِ ﷺ فَقَالَ «مَا شَأْنُكُمْ تُشِيرُونَ بِأَيْدِيكُمْ كَأَنَّهَا أَذْنَابُ خَيْلٍ شُمْسٍ؟ إِذَا سَلَّمَ أَحَدُكُمْ فَلْيَلْتَفِتْ إِلَى صَاحِبِهِ وَلَا يُومِئُ بِيَدِهِ»