I heard the Messenger of Allah ﷺ say: The official who collects sadaqah (zakat) in a just manner is like him who fights in Allah's path till he returns home.  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ الْعَامِلُ عَلَى الصَّدَقَةِ بِالْحَقِّ كَالْغَازِي فِي سَبِيلِ اللَّهِ حَتَّى يَرْجِعَ إِلَى بَيْتِهِ  

I heard the Messenger of Allah ﷺ as saying: One who wrongfully takes an extra tax (sahib maks) will not enter Paradise.  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ قَالَ لاَ يَدْخُلُ الْجَنَّةَ صَاحِبُ مَكْسٍ  

Sahib maks means one who (receives) tithes (from) people.  

الَّذِي يَعْشُرُ النَّاسَ يَعْنِي صَاحِبَ الْمَكْسِ