Good deeds add strength to overcome Esav

בפסוק כאשר ילדה רחל את יוסף ויאמר שלחני כו' וברש"י בית יוסף להבה כו'.

On the pasuk: "When Rachel bore Yosef, [Yaakov] said, 'Send me away…'" and Rashi [comments]: "the house of Yosef a flame…"

Only after Yosef was born did Yaakov feel ready to leave Lavan and face Esav; Rashi explains, citing the navi, that Yosef is the "flame" that consumes the "straw" of Esav.

דכתיב כחצים ביד גבור כן בני הנעורים.

As it is written: "Like arrows in the hand of a warrior, so are the children of one's youth."

Children are compared to arrows — a weapon that reaches far beyond where the warrior himself can stand.

ומצינו שיעקב אע"ה ברח ללבן מפני עשו וכשהוליד בניו חזר.

And we find that Yaakov Avinu fled to Lavan because of Esav, and when he had fathered his children he returned.

The very thing that emboldened Yaakov to return and confront Esav was the birth of his children.

וביאור הענין הוא כי הקב"ה נתן כח באדם וצריך להוציאו מכח אל הפועל כמ"ש אשר ברא אלקים לעשות.

And the explanation of the matter is that Hashem placed a potential within a person, and one must bring it from the potential into the actual, as it says: "which Elokim created to do."

"To do" means creation was left unfinished on purpose — each person carries latent powers that he is meant to actualize through his own deeds.

שנתן כח בכל הברואים שיתפשטו ויפרו וירבו.

For He placed a power within all creatures to spread out and to be fruitful and multiply.

Every created thing was given the capacity to extend itself and increase.

וכפי התולדות שמתרבה מאדם כמו כן מתרבה כח שרשו.

And according to the offspring that multiply from a person, so too the power of his root is multiplied.

As one's descendants grow, the spiritual strength of one's own source expands along with them.

וכפי השפעתו כך משפיעין לו.

And according to how much one bestows, so is bestowed upon him.

The more a person gives forth and produces, the more Heavenly influence flows back to him.

וכמו שכן בתולדות כן בפעולות מעש"ט שכ' ז"ל עיקר תולדותיהן של צדיקים מצות ומעש"ט.

And just as this is so with offspring, so it is with actions — mitzvos and good deeds — for Chazal said: "the primary 'offspring' of the tzaddikim are mitzvos and good deeds."

The same law of multiplication applies to a person's spiritual "children": his mitzvos and maasim tovim, which Rashi (on "these are the toldos of Noach") calls the true progeny of the righteous.

וכלל הענין שלבד החלק שניתן לכל אדם.

And the principle of the matter is that, beyond the portion given to each person,

Every person receives a fixed measure of innate spiritual strength.

יש בכחו למצוא תוספות כח ע"י תיקון המעשים.

he has the ability to find an additional power through the rectifying of his deeds.

Through good actions a person can acquire an extra, added strength beyond his original portion.

וזה הכח נקרא יוסף.

And this power is called "Yosef."

Yosef — whose name means "He shall add" — represents this added, self-acquired spiritual power.

וע"ז נאמר כשנולד לו כח התוספות הנ"ל לא ירא שוב מעשו.

And concerning this it is said that when this added power was born to him, he no longer feared Esav.

Once Yaakov attained the "added power" embodied in Yosef, Esav held no more terror for him.

וזה נדמה ללהבה שהולך יותר מרחוק.

And this is compared to a flame, which travels farther.

This added strength is like a flame that reaches distances the person himself could never travel.

כמו כן התרחבות המעשים הם כלי זיין של אדם במה שהוא עצמו אינו יכול להגיע לשם.

So too the expansion of one's deeds is a person's weaponry, reaching to where he himself cannot arrive.

A person's accumulated good deeds act like arrows or armor, extending his spiritual reach far beyond his own limited self.

נמצא הלך יעקב לחרן למצוא כלי זיין וחצים הנ"ל:

It emerges that Yaakov went to Charan to acquire this weaponry and these arrows.

Yaakov's journey to Lavan was, in essence, a mission to gain his "arrows" — the children and added powers that would arm him to overcome Esav.

Summary: Yaakov could face Esav only after fathering his children, who are like "arrows" reaching beyond the warrior himself. Hashem implants latent power in every person that must be actualized; beyond one's fixed portion, mitzvos and good deeds generate an added strength — embodied in Yosef ("He shall add"), the "flame" that reaches far. Yaakov went to Charan precisely to acquire these spiritual weapons that would let him overcome Esav.