Who knows thirty-eight?
Please cite/link your sources, if possible. After about one business day, I will:
Upvote all interesting answers.
Accept the best answer.
Go on to the next number.
38 are the years during which the Jewish People were "nezufim," under a Divine ban (from the 9th of Av 2449, after the sin of the Spies, to the 15th of Av 2487).
During this time, too, Hashem's communications with Moshe were not with the same degree of closeness as before and after. This teaches us that all prophets, Moshe included, have the Divine Presence rest on them for the sake of the Jewish People, not because of their own personal merits. (Deut. 2:14-17, and Rashi on 16)
Thirty-eight are the categories of forbidden labor on Sabbath for which the death penalty can be given, according to R' Yosei. (Shabbos 70a)
38 is the age to which the Arizal lived. (He was born in 5294/1534, and passed away on the 5th of Av 5332/1572.)
And look how much he accomplished in that short amount of time!
38 are the verses in Chaggai.
Thirty-eight is the age which Rabbi Nachman of Breslov lived. He was born on Rosh Chodesh 5532 and died 18 Tishrei 5571, which corresponds to April 4, 1772 to October 16, 1810 in secular dates.
He is famous for being the first and only Breslover Rebbe, and for instituting the Tikkun HaKlali, ten psalms for spiritual rectification of sexual sins. His biography and teachings were written down by the most dedicated student, R' Nosson of Breslov, in Chayei Moharan and Likutei Moharan.
38 is the gematriah of wet. (lah)
(I'm running dry on number associations!)
Abraham outlived Sarah by 38 years.
There are 38 grandchildren of Avraham named in Sefer HaYashar. They are:
נבית קדר אדבאל מבשם משמע דומה משא חדד תימא יטור נפיש קדמה בשמת אדום/עשו ישראל/יעקב אביהן מוליך מרים ערבת שבא דדן אמידע יוב גוחי אלישע נותח עיפה עפר חנוך אבידע אלדעה מכירי בידוע סתור בלדד חמדד מושן מיכן
The grandchilren (except for ערבת) of Avraham and Keturah appear in Chapter 25. ערבת appears in Chapter 45 as the second wife of Binyomin. The twelve sons of Yishmoel are found in Chapter 25 and also in Shvi'i of Chayei Sarah. בשמת appears as one of Esau's wives. Also Yokshan and Midian's sons appear in Chayei Sarah Shishi.
38 is the gematria of the word בול, the name given to the month of Cheshvan (Melachim alef 6:38)