New Defender's Study Bible Notes
5:22 Raca. The word raca is an Aramaic expression of contempt, something like our English “stupid idiot!” Such an insult to a fellow believer in the Jewish economy might warrant being charged, before the council of the Sanhedrin, with slander.
5:22 Thou fool. This is even a greater insult. The Greek is the word from which we get our English word “moron,” but it also conveys an implication of rebellion. For a believer to call a brother a “rebellious moron” would be so out of character as to imply that the one using such language might not even be a true believer.
5:22 hell. “Hell” is gehenna, in the Greek, the place of everlasting fire. Almost certainly it refers to the ultimate lake of fire (Revelation 20:15), not to the great pit in the center of the earth known as hades (this word is also commonly translated “hell”—e.g., Matthew 11:23), where the spirits of the unsaved are confined as they await the final judgment. Note the divine principle implied in this verse of degrees of punishment.