21 I have given her time to repent, but she is not willing to repent of her sexual immorality. 22 Look! I am throwing her onto a bed of violent illness, and those who commit adultery with her into terrible suffering, unless they repent of her deeds. 23 Furthermore, I will strike her followers with a deadly disease, and then all the churches will know that I am the one who searches kidneys^* and hearts. I will repay each one of you what your deeds deserve. 24 But to the rest of you in Thyatira, all who do not hold to this teaching (who have not learned the so-called “deep secrets of Satan”), to you I say: I do not put any additional burden on you. 25 However, hold on to what you have until I come.

The Sages taught in a baraita: A person has two kidneys; one advises him to do good and one advises him to do evil. And it stands to reason that the one advising him to do good is to his right and the one that advises him to do evil is to his left, as it is written: “A wise man’s understanding is at his right hand, but a fool’s understanding is at his left” (Ecclesiastes 10:2). Tangential to the subject of kidneys, the Gemara cites that which the Sages taught in a baraita with regard to the roles of various organs: The kidneys advise, the heart understands, the tongue shapes the sounds that emerges from the mouth, the mouth completes the shaping of the voice, the esophagus takes in and lets out all kinds of food, the trachea produces the voice,