Midras Mazmur 69:14: Ein Yaakov (Glick Edition), Devarim Rabbah, Eikhah Rabbah & Midrash Tanchuma

R. Isaac said to R. Nachman: "Why did not the master come to the synagogue to pray?" "Because I was not feeling well," answered R. Nachman. "The master should have gathered ten in his house and then prayed," said R. Isaac. "It was too hard a task for me," said R. Nachman. "If so," remarked R. Isaac, "then why did not the master direct the Sexton to inform him when the public pray? [so that he might pray at that time?]" "Why are you so particular about it?" asked R. Nachman, "Because," said R. Isaac, "R. Jochanan in the name of R. Simon b. Jochai said: (Fol. 8a) 'What is meant by the passage (Ps. 69, 14.) But as for me, I direct my prayer unto Thee, O Lord, in a time of favor. When is it a time of favor? It is when the community at large prays.'" R. Jose, the son of Chanina said: "We infer it from this, (Isa. 49, 8.) Thus hath said the Lord, in the time of favor have I answered thee." R. Chanina said: "We derive it from this, (Job 36, 5.) Behold, God is mighty and despiseth no one, and it is written (Ps. 55, 19.) He delivered my soul in peace from the battle against me; for in multitudes are they (contending) with me." We have also a Baraitha to the same effect, R. Nathan said: "Whence do we know that the Holy One, praised be He! despiseth not the prayers of a community? It is written (Job 36, 5.) Behold God, many He doth not despise, and it is written (Ps. 55, 19.) He delivereth my soul in peace from the battle against me; for in multitudes, etc., i.e., the Holy One, praised be He! says: 'When any one occupies himself with the study of the Torah and the practice of loving kindness I consider as if he delivered me and my children from the nations.' "

Another matter: “As is the Lord our God” – this is what the verse said: “But as for me, let my prayer come to You, Lord, at a time of favor” (Psalms 69:14). Rabbi Ḥanina bar Pappa asked Rabbi Shmuel bar Naḥman: ‘What is [the meaning of] that which is written: “But as for me, let my prayer come to You, Lord, at a time of favor”?’ He said to him: ‘The gates of prayer are sometimes open and sometimes locked, but the gates of repentance are always open.’ [Rabbi Ḥanina] said to him: ‘From where is this derived?’ [He answered:] ‘As it is written: “You answer us justly with awesome deeds, God of our salvation, shelter of all ends of the earth and the farthest sea” (Psalms 65:6) – just as a ritual bath is sometimes open and sometimes locked, so, the gates of prayer are sometimes open and sometimes locked. But just as the sea is always open, so, the hand of the Holy One blessed be He is always open to accept penitents.’ Rav Anan said: The gates of prayer, too, are never locked, as it is written: “As is the Lord our God in all of our calling [korenu] to Him.” Calling is nothing other than prayer, as it is stated: “It will be, before they call, I will answer” (Isaiah 65:24). Rabbi Ḥiyya Rabba said: It is written: “Put your hope in the Lord; be strong and let your heart take courage, and put your hope in the Lord” (Psalms 27:14) – pray, and pray again, and there will be a time when it will be granted to you.
Another matter: “But as for me, let my prayer [come to You, Lord, at a time of favor]” (Psalms 69:14) – David, because he was an individual, said: “A time of favor.” But the prayer of the community never returns unanswered. That is, “as is the Lord our God in all of our calling to Him.”

What is, “in all of our calling to Him”? The Rabbis said: There is prayer that is answered after forty days. From whom do you derive this? From Moses, as it is written: “I fell before the Lord, as at the first, forty days…” (Deuteronomy 9:18).³³The following verse concludes: “And the Lord heeded me that time as well” (Deuteronomy 9:19). There is prayer that is answered after twenty days. From whom do you derive this? From Daniel, as it is written: “I ate no tasty bread…until the completion of three weeks of days” (Daniel 10:3), and then he said: “Lord, hear; Lord, forgive…” (Daniel 9:19). There is prayer that is answered after three days. From whom do you derive this? From Jonah, as it is written: “Jonah was in the innards of the fish [for three days and three nights]” (Jonah 2:1). And then: “Jonah prayed to the Lord his God from the innards of the fish” (Jonah 2:2). There is prayer that is answered after one day. From whom do you derive this? From Elijah, as it is written: “[It was at the time of offering up the afternoon offering] that Elijah the prophet approached, and he said…[Today it will be known that You are God in Israel]” (I Kings 18:36). There is prayer that is answered after one time period.³⁴This is one twelve-hour period, either one day or one night. From whom do you derive this? From David, as it is written: “But as for me, let my prayer come to You, Lord, at a time of favor” (Psalms 69:14). There is a prayer that even before it is expressed from his mouth, the Lord will answer, as it is stated: “It will be, before they call, I will answer” (Isaiah 65:24).