John Chrysostom — as excerpted in the Catena Aurea on Matthew 5:20-22

“Or, Racha is a word signifying contempt, and worthlessness. For where we in speaking to servants or children say, Go thou, or, Tell thou him; in Syriac they would say Racha for ‘thou.’ For the Lord descends to the smallest trifles even of our behaviour, and bids us treat one another with mutual respect.”