Midrash sur L’Exode 33:20

He said I am the God of your father. This is as it is written, "A fool will believe anything...". "Peti" is the language of seduction (pituy) as it says, "when a man seduces" (yifteh). R. Yehoshua the Kohen b. Nehemiah said, When the Holy Blessed One revealed Himself to Moshe he was a prophetic novice. The Holy Blessed One said, If I reveal Myself to him in a great voice I will frighten him, with a small voice I will sour him on prophecy. What did He do? He revealed Himself to him with the voice of his father. Moshe said, "Here I am! What does father ask?" The Holy Blessed One said, "I am not your father, rather I am the God of your father. I came to you with seduction so that you would not be afraid."

(Fol. 49b) We are taught that Ben Azai says: "I found a secret scroll wherein it was written that a certain man was a Mamzer. It was also written there that the Mishnath of R. Eliezer b. Jacob is only a Kab (little in quantity), but well sifted. It was also written there that M'nashe executed Isaiah (the prophet)." Raba said: "He was tried before a court (of false prophets) where he was executed. He was asked: 'Moses thy master said (Ex. 33, 20) For no man can see me and live, and you said (Is. 6, 1) I saw the Lord sitting upon a high and exalted throne. Moses your master said (Deut. 4, 7) Who hath God so nigh unto it, as is the Lord our God at all times that we call upon Him, and you said (Is. 55, 6) seek ye the Lord, while He may be found. Moses your master said (Ex. 23, 26) The number of thy days will I make full, and you said (Is. 38, 5) I will add unto thy days fifteen years.' Isaiah then said to himself: I am quite sure that even should I offer him any explanation he will not accept it. If so, then why should I offer it altogether since it would merely cause him to commit [his crime] wilfully? Thereupon he uttered the Tetragrammaton and was swallowed up by a cedar tree. They brought the cedar and sawed it through, and when the saw reached Isaiah's mouth he died, because [of the sin he committed with his mouth when] he said (Is. 6, 5) "And in the midst of a people of unclean lips do I dwell."

R. Yohanan declared: Woe unto us on judgment day, woe unto us on the day of rebuke, for if Joseph could cause them to faint by saying “I am your brother Joseph,” what will happen when the Holy One, blessed be He, arises to judge us, since it is written about Him: Who may abide the day of His coming? And who shall stand when he appeareth? (Mal. 3:2), and For no man shall see Me and live (Exod. 3:20)? If a mere human could confound his brothers, how much more so will we be confounded when the Holy One, blessed be He, examines us concerning our arrogance toward the commandments and our transgressions of the Torah.