“But on the last day of the feast which was the most glorious one Jesus appeared and cried and said: “If anyone thirsts, let him come to me and drink.””
The Lord Christ wanted to say here: “So far, you have never received a drop from all your teachers, preachers, and priests so as to comfort you and to quench your thirst. There has been nothing but a harried, tortured, and frightened conscience that was thirsty to the point of dying of thirst.” There has not been anyone who could have comforted, as there is today little comfort under the sectarian spirits and the papist bishops. This is why the Lord Christ says: “I preach a different teaching to you that is to make you alive, refresh you, give you drink who are thirsty, who are also desperate, frightened, and full of doubt and uncertainty in your conscience about your relationship with God. Just come here. I will not hit you on the head with a club or gouge out your eyes. Come to me. I will give you drink. That is to say, in me and through me you will find the teaching that will comfort and strengthen your heart and take away doubt and give you certainty that you are in a good relationship with God.” These, then, are the two parts we preach about: The law makes thirsty and leads to hell and kills. The gospel, however, provides drink and leads to heaven. The law says what we should do and that we have not done it, no matter how holy we are. This is how it makes me uncertain about my salvation and drives me into thirst. … When you realize that you do not love God wholeheartedly, as you well should, you must confess and say: “O dear God, I have not done this. I have not kept the law, because I love God neither today nor tomorrow and confess every year the same thing, namely, that I have done this and that.” This confession does not want to cease – when will it end? When will your heart rest and be secure in divine grace? You always remain in doubt. Tomorrow you confess just as you did today. The common confession always remains. Now, where do you want to rest? Where is the foundation for your conscience so you may know what your relationship with God is like? Your heart cannot tell you, do whatever you can do. For the law remains that says: “You shall love God and man from all your heart.” But you say: “I do not do this.” Then the law says: “You shall do it.” This is, then, how the law makes me afraid so that I must become thirsty, frightened, and trembling, saying: “What will I do so that God looks at me in grace? Am I to obtain God’s grace when I keep the Ten Commandments, when I have good works and many merits? But that never happens. I do not keep the Ten Commandments. This is why grace never finds me.” This is why it turns out that man cannot find rest in good works although he would like to have a good conscience. He gains a desire to obtain a good, joyous, peaceful, comforted conscience. He thirsts for being at peace. This is called the thirst. It lasts until Christ comes and says: “If you would like to be at peace, have rest and a good conscience, I advise you to come to me and let go of Moses and works. Make a distinction between me and Moses: Moses has made you thirsty. He has done his job and carried out his office, making you frightened and thirsty. Now come also to me. Believe in me. Listen to my teaching. I am a different preacher. I will give you drink and refresh you.”
St. Louis ed., 8:80-82.