When the Messenger of Allah ﷺ sat talking (to the people), he would often raise his eyes to the sky.  

كَانَ رَسُولُ اللَّهِ ﷺ إِذَا جَلَسَ يَتَحَدَّثُ يُكْثِرُ أَنْ يَرْفَعَ طَرْفَهُ إِلَى السَّمَاءِ  

The Messenger of Allah ﷺ spoke in a distinct and leisurely manner.  

سَمِعْتُ جَابِرَ بْنَ عَبْدِ اللَّهِ يَقُولُ كَانَ فِي كَلاَمِ رَسُولِ اللَّهِ ﷺ تَرْتِيلٌ أَوْ تَرْسِيلٌ  

The Messenger of Allah ﷺ spoke in a distinct manner so that anyone who listened to him could understand it.  

كَانَ كَلاَمُ رَسُولِ اللَّهِ ﷺ كَلاَمًا فَصْلاً يَفْهَمُهُ كُلُّ مَنْ سَمِعَهُ  

The Prophet ﷺ said: Every important matter which is not begun by an expression of praise to Allah is maimed. Abu Dawud said: It has also been transmitted by Yunus, 'Aqil, Shu'aib, Sa'id b. 'Abd al-Aziz from al-Zuhri from the Prophet ﷺ in Mursal form (the link of the Companion is missing).  

قَالَ رَسُولُ اللَّهِ ﷺ كُلُّ كَلاَمٍ لاَ يُبْدَأُ فِيهِ بِ الْحَمْدُ لِلَّهِ فَهُوَ أَجْذَمُ