To the conductor, with stringed instruments. A psalm of David. When I call, answer me, O my righteous God. R. Yitzchak says: everything that David said, he said about himself and about all Israel. "My God, my righteousness, on You I rely; vindicate me!" Why is it that I, from the tribe of Judah, call to You, when You hear the prayer of the tribe of Judah, as it says (Deuteronomy 33:7), "Hear, O Lord, the voice of Judah." The rabbis say: The congregation of Israel said in "When I call," "Vindicate me; if I am without merit, do it for the sake of charity with me." Rabbi Yehoshua ben Levi said: Since David said, "When I call, answer me," I only have a response when the Temple is built. Whence do we learn this? From the phrase, "When I call," which implies, "Whenever I call."