en_tn_condensed/mat/06/02.md

do not sound a trumpet before yourself

This metaphor means to do something that purposefully gets people's attention. AT: "do not draw attention to yourself like someone who plays a loud trumpet in a crowd" (See: rc://en/ta/man/translate/figs-metaphor)

Truly I say to you

"I tell you the truth." This phrase adds emphasis to what Jesus says next.