Paul uses a question to introduce the next part of his message. Alternate translation: "Because everything I have just told you is true, this is what you need to do, my fellow believers." (See: [[rc://en/ta/man/translate/figs-rquestion]])
This means to tell what someone has said in a language to others who do not understand that language. See how "interpret" is translated in [1 Corinthians 2:13](../02/12.md).