Midrasch zu Bereschit 33:4

“Your neck is like an ivory tower; your eyes are pools in Ḥeshbon, by the gate of Bat Rabim; your nose is like the tower of Lebanon overlooking Damascus” (Song of Songs 7:5).
“Your neck is like an ivory tower.” It is written: “Esau ran to meet him, embraced him, fell upon his neck, and kissed him [vayishakehu] [and they wept]” (Genesis 33:4). The entire word³²The word vayishakehu is written in the Torah scroll with a dot over each of the letters. is dotted. Rabbi Shimon ben Elazar said: Everywhere that you find the script more numerous than the dots, adopt the script and ignore the dots. If the dots are more numerous than the script, adopt the dots and ignore the script. However, here, neither is the script more numerous than the dots, nor are the dots more numerous than the script, but rather it is dotted above vayishakehu in its entirety. This teaches that he did not come to kiss him, but rather to bite him. Jacob’s neck became as hard as marble and the teeth of that wicked one became dull and melted like wax. Why does the verse state: “And they wept”? This one was crying over his neck, and that one was crying over his teeth.
Rabbi Abahu in the name of Rabbi Elazar cites it from this: “Your neck is like an ivory tower.” It is written: “Pharaoh heard this matter and he sought to kill Moses. Moses fled” (Exodus 2:15). Is there a person who is able to flee from the king? Rather, it teaches that he was standing and was sentenced on that same day, and they condemned him to beheading. Rabbi Evyatar said: The sword glanced off the neck of Moses and sliced the neck of the wicked executioner. That is what is written: “For the God of my father was my help, and He delivered me from the sword of Pharaoh” (Exodus 18:4). He delivered me, but did not deliver the executioner. Rabbi Bon would apply to him the verse: “The righteous is extricated from trouble, and the wicked comes in his place” (Proverbs 11:8). Rabbi Berekhya said: “The wicked is ransom for the righteous” (Proverbs 21:18). Bar Kappara said: It teaches that an angel descended in the guise of Moses, and they apprehended the angel and left Moses, and he fled. Rabbi Abba son of Rav Pappi and Rabbi Yehoshua of Sikhnin [said] in the name of Rabbi Levi: At that moment all of Pharaoh’s advisors, some of them became mute, some of them deaf, some of them blind, and some of them disabled. They said to the mutes: Where is Moses? But they could not speak. To the blind, but they could not see. To the deaf, but they could not hear. To the disabled, but they could not walk, as it is stated: “The Lord said to him: Who gives a mouth to a person, or who renders one mute or deaf, or sighted or blind? Is it not I, the Lord?” (Exodus 4:11). Is it not I who did all these? “Now go and I will send you to Pharaoh” (Exodus 3:10).

When Jacob passed to come into the land of Canaan, Esau came to him from Mount Seir in violent anger, contriving to slay him, as it is said, "The wicked plotteth against the just, and gnasheth upon him with his teeth" (Ps. 37:12). Esau said: I will not slay Jacob with bow and arrows, but with my mouth and with my teeth will I slay him, and suck his blood, as it is said, "And Esau ran to meet him, and embraced him, and fell on his neck, and kissed him; and they wept" (Gen. 33:4). Do not read vayishakêhu (and he kissed him), but (read) vayishkêhu (and he bit him). But Jacob's neck became like ivory, and concerning him the Scripture says, "Thy neck is like the tower of ivory" (Cant. 7:5). The wicked (Esau's) teeth became blunt, and when the wicked one saw that the desire of his heart was not realized he began to be angry, and to gnash with his teeth, as it is said, "The wicked shall see it, and be grieved; he shall gnash with his teeth, and melt away" (Ps. 112:10).

Esav ran to greet him. [He embraced Yaakov and, falling on his neck,] he kissed him; [and they wept.] (Gen. 33:4). [The word] 'kissed' is dotted [above each letter in the Torah's writing]. Rabbi Shimeon ben Elazar said in every place that you find a lot of text with few dots on top, you need to interpret the dots; when you find a lot of dots on top of a few words you interpret the words. Here neither is the case, rather it teaches that [Esav] was overcome with compassion in that moment and kissed [Yaakov] with all his heart. Rabbi Yannai said to him: If so, why is ['kissed'] dotted? On the contrary, it teaches that [Esav] came not to kiss [Yaakov] but to bite him, but our ancestor Yaakov's neck became like marble and that wicked man's teeth were blunted. Hence, 'and they wept' teaches that [Yaakov] wept because of his neck and [Esau] wept because of his teeth. Rabbi Abahu, in the name of Rabbi Yochanan teaches that from here: "your neck is like the tower of ivory" (Songs 7:5)