Midrash sobre Gênesis 21:5

From Adam to the Flood was 1656 years, and this is their enumeration: Adam 130, Seth 105, Enosh 90, Kenan 70, Mahalalel 65, Jared 162, Enoch 65, Methuselah 187, Lamech 182, and Noah was six hundred years old, etc." (Genesis 7, 6). Enoch buried Adam, and lived after him 57 years. Methuselah exhausted his days just before the Flood. From the Flood to the division [of languages] was 340 years. Noah lived ten years after the division [of languages]. Our father Abraham was at the division [of languages] 48 years old. Rabbi Yosei said: Eber was so great a prophet that he [preemptively] named his son Peleg ["division"], [aided] by the Holy Spirit. [Eber having foreseen what was to come] as it says "in his days the earth was divided" (Genesis 10, 25).

R. Abin said: Abraham may be likened to a flask of oil that had been hidden away in a cemetery, the fragrance of which was unknown to anyone. What did they do with it? They removed it from the cemetery and carried it about from place to place until its fragrance became familiar throughout the world. This happened to Abraham. He dwelt among idolaters, and so the Holy One, blessed be He, commanded him: Get thee out of thy country, and from thy kindred in order that I may make thy nature known throughout the world. Get thee out of thy country. What is the meaning of lekh lekha (“get thee out”)? Each lamed in these words equals thirty, and each kaf equals twenty, totaling one hundred in all; thereby hinting to Abraham: When you become one hundred years old, you will beget a righteous son, as it is written: And Abraham was one hundred years old when his son Isaac was born to him (Gen. 21:5).

(Gen. 24:1, cont.:) AND THE LORD HAD BLESSED ABRAHAM IN EVERYTHING. What is the meaning of IN EVERYTHING (BKL)? While he was between the < sacrificial pieces (in Gen. 15), he brought him the good news that he would give him a son fifty-two years later.²²The letters in BKL total 52. How so?²³According to Gen. 21:5, Abraham was one hundred when Isaac was born. R. Johanan and R. Hanina say: At the age of forty-eight Abraham came to know his Creator.²⁴Gen. R. 30:8; 46:2; 64:4; but cf. 95:3; above, 3:4; Cant. R. 5:16:1; PR 21:12. At that time he gave him the good news that he would give him a son fifty-two years later. Ergo (in Gen. 21:1): AND THE LORD HAD BLESSED ABRAHAM IN EVERYTHING.