Jesus is emphasizing that what he has just said is important and may take some effort to understand and put into practice. The phrase "has ears" is a metonym for being willing to understand and obey. Alternate translation: "Whoever is willing to listen, listen" or "Whoever is willing to understand, let him understand and obey" (See: [[rc://en/ta/man/jit/figs-metonymy]])
Since Jesus is speaking directly to his audience, you may prefer to use the second person here. Alternate translation: "If you have ears to hear, then hear" or "If you are willing to understand, then understand and obey" (See: [[rc://en/ta/man/jit/figs-123person]])