Another interpretation of the eighth [day of Passover] is in regards to the four kingdoms that are eight, and Edom is the eighth. This is what is written (Daniel 2:32-33): "Its head was of fine gold, its breast and arms of silver, its belly and thighs of bronze, its legs of iron, its feet part iron and part clay." There are thus eight, which are four: Babylon & Chaldea, Media & Persia, Greece & Macedonia, and Edom & Yishmael.
There are thus eight kingdoms, which is why [the eighth day] is mentioned. Rabbi Ibu said: The Assembly of Israel said before the Holy One, blessed be He, "Master of the Universe, we praise You at the time when You save us from the eight kingdoms, as it is said (Isaiah 11:11), 'And it shall come to pass on that day that the Lord shall set His hand again the second time to acquire the remnant of His people.'”
This is why [the eighth day] is mentioned. Rabbi Yudan said in the name of Rabbi Ami: The Assembly of Israel said before the Holy One, blessed be He, "Even though it is written about me (Proverbs 3:12), 'For whom the Lord loves He reproves, even as a father the son in whom he delights,' still, 'Do not discipline me in Your anger' (Psalm 38:2). Even though it is said (Psalm 94:12), 'Happy is the man whom You chasten, O Lord,' 'Do not discipline me in Your wrath.'”
Rabbi Yochanan gave a parable: It is like a king who had two evil advisors, and whenever any province rebelled against him, he would send them to suppress it. Once his own province rebelled against him, and he wanted to send those advisors to suppress it. They began to beg him, "Our master the king, in everything that you want, we will do, except for this." So too did Israel say to the Holy One, blessed be He, "Do not discipline me in Your anger, and do not chasten me in Your wrath."
He said to them, "If so, why do I need anger and wrath?" They said to him, "You have to whom to send [Your anger and wrath]." As it is written (Micah 5:14), "I will execute vengeance in anger and wrath upon the nations." But regarding Israel, what is written? (Hosea 11:9) "I will not execute the fierceness of My anger."
Rabbi Elazar said a parable about a king who was angry with his son, and he had a drawn sword in his hand and swore that he would kill him for making him angry. The king said, "If I kill my son, then he will have no one to inherit my kingdom after me, and also, I cannot revoke my decree." What did the king do? He put the sword in its sheath and passed it over his own head.
In this way, he did not harm his son, and also, he did not revoke his decree. Rabbi Chanina said a parable about a king who was angry with his son, and there was a large stone before him, and he swore that he would throw it at him. The king said, "If I throw the stone at him, he will be killed." What did the king do?
He broke the stone into small pieces and threw them one by one. In this way, he did not harm his son, and also, he did not revoke his decree. The sages said a parable about a king who was angry with his son, and he swore that he would strike him with a hundred lashes. The king said, "If I strike him, he will be killed."
What did the king do? He took the rope and put it around his own neck. Therefore, it says, "In your anger, you chastised me." (Psalms 38:2)