The Wisdom of Israel, by Edwin Collins, , at sacred-texts.com
"And thou shalt return unto the Lord thy God."
Rabbi Samuel of Pargreeta says in the name of Rabbi Meir: "To what may this be likened? To the son of a king who went away from home and turned to evil ways; and the king sent a tutor to him with a message, saying, 'Return, my son.' And the son sent him back with the answer, 'How can I come back to thee, oh sire, to be put to shame before thee?' Then the king sent again to him, saying, 'Can a son be ashamed to come back to his father, and if thou dost return is it not to thine own father that thou dost return?'" In like manner, when God sent messages to Israel by the prophets, telling them to repent, and they were ashamed by reason of their sins, Jeremiah was sent to tell them, "If you return, it is to a loving father that you are returning (Jer. xxxi.), for I have been a father unto Israel."
Rabbi Channanya bar Papa asked Rabbi Samuel bar Nachman, what is the meaning of the verse (Psalm), "As for me I will offer my prayer unto Thee in an acceptable time "? He replied, "The gates of prayer are sometimes open and sometimes closed, but the gates of repentance are always open." It is like the difference between a gathering together of waters made by man, and the great open sea. The waters that man has drawn together reflect the face of heaven
when they are not dried up, and the man-made Mikveh * will cleanse one from impurity, but it is sometimes closed: the vast ocean is always open. It always reflects the light of heaven, and all may bathe therein at any time.
So the hand of the Holy One, blessed be He, is at all times stretched out to receive the repentant (those that return). Rabbi Onon says, "Also the gates of prayer are always open."
41:* Mikveh is a bath in which living water flows. Such baths are made for every Jewish congregation, and used on all occasions when the ceremonial or hygienic law requires the taking of a bath.