Who knows four?
Please cite/link your sources, if possible. After Shabbat, I will:
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Four is number of angels, faces, wings and hands (on each angel) of Yechzkiel's vision
Four are the fasts for the Mikdash.
(Hat-tip: my daughter)
Four are the cardinal directions:
Four are the corners of the Mizbeahh.
There are 2 which are subdivided into FOUR ways to move something from a private domain to a public domain on Shabbos (Shabbos Mishna 1:1)
4 exiles: בבל, פרס ומדי, יון. אדום.
These correspond to the letters of the word גשנה, which stands for גוף שכל נפש הכל.
גוף corresponds to גלות פרס ומדי.
שכל corresponds to גלות יון.
נפש corresponds to גלות בבל.
הכל corresponds to גלות אדום.
This is also connected to the 4 sides of the דריידל.
There are 4 sons of יבן (see 1 Chronicles 1:7 and Genesis 9:4)
There are 4 sons of חם (see 1 Chronicles 1:8 and Genesis 9:6)
There are 4 sons of ארם (see Genesis 9:23)
There are 4 sons of ראואל (see 1 Chronicles 1:37)
There are 4 sons of ראומה (see Genesis 22:24)
There are 4 types of creations: Domem (like stones), Tsomeach (plants), Chai (animals), and Medaber (humans).
Four is the lowest age of chinuch for standard mitzvos.
Four are the number of ages at which Chazal recommend that one should get married, each one more optimal than the next:
Fourteen, Sixteen, Eighteen and Twenty.
There are four people called Chanoch in the Torah. Chanoch son of Kayin (Bereishis 4:17), Chanoch son of Yered (Bereishis 5:18), Chanoch son of Midyan (Bereishis 25:4), and Chanoch son of Re'uvein (Bereishis 46:9). As you can see, all four of these are found in Seifer Bereishis.
There are four things called “two which are four,” all of which are found in the first Mishnah of Shevuos. The below sources indicate other places where the teachings appear.
4 sons referenced in the Haggadah: חכם, רשע, תם and שאינו יודע לשאול.
4 relationships with Hashem referenced in ידיד נפש: master-servant, romantic love, father-son, friendship.
4 types of worshippers referenced at the end of פסוקי דזמרה of Shabbos: ישרים, צדיקים, חסידים and קדושים.
-...commoners have no share in the World to Come: Balaam, Doeg, Ahithophel and Gehazi. (Sanhedrin 90a)
...vessels Hashem knocked and found to be full of urine (worthless): Adam, Cain, Balaam, and Hezekiah. (Breshis Rabbah 19:11)
Biblical figures who vowed, 2 incurred loss (Yaakov and Jephtah) and the other 2 profitted (Hannah and Klal Israel) - Bereshit Rabbah 70:4