Rachel’s Plea
The Matriarch Leah bears four children for which she expresses profound gratitude. Her sister and co-wife Rachel is chagrined because she is childless. The Torah describes her feelings and actions thus:
“Rachel saw that she had not borne children to Jacob, so Rachel became envious of her sister. She said to Jacob, ‘Give me children – otherwise I am dead.’
Jacob’s anger flared up at Rachel, and he said, ‘am I instead of G‑d who has withheld from you fruit of the womb?’”
Several questions have been raised about this brief exchange between Jacob and his beloved wife Rachel:
First, how could the supremely righteous Rachel be envious of her sister?
Rashi explains that she was envious of Leah’s good deeds, ascribing her co-wife’s   fecundity to righteous behavior.
The question however remains, why does the Torah have to link her request for children to her envy of her sister’s good deeds? Even if her sister had not been blessed with children, Rachel would still have desired children of her own!
Second, why did the otherwise righteous and compassionate Jacob lash out at his wife with undisguised anger? True, the Midrash states that G‑d took him to task for this, but, can we understand what motivated him, one whom the Sages described as “G‑d’s chariot,” meaning that he had totally subordinated his will to the will of G‑d. What G‑dly justification could there have been for his anger?
Third, Rashi explains that Jacob’s anger was motivated by his belief that he could not pray for her because he already had children. Ramban is puzzled by this explanation. Why couldn’t Jacob pray that his wife should bear children? Where does it say that one may only pray for his own needs?
Craving Children
To answer these questions we must begin by considering a statement made by our Sages (Talmud, Yevamos 64a) explaining why the Matriarchs were initially unable to bear children: “G‑d desires the prayers of the righteous.” Ordinarily, righteous people do not ask G‑d for anything material because they are happy with whatever blessings G‑d bestows upon them. They are happy and grateful just to be alive and serve G‑d. They crave nothing more, with one notable exception. Even the most ascetic and self-denying saint wants children.
One may suggest three reasons for this phenomenon:
First, the righteous person wants to give of self and nurture others.  They cannot imagine a life which deprives them of the ability to share their blessings. And since there is no parallel to the love and nurturing given to one’s own child, the righteous crave parenthood.   Just listen to Rachel, who stated, “Give me children, otherwise I am dead.” To Rachel life without a child was not life in the true sense of the word.
Second, a righteous person devotes his or her life to bringing G‑dly energy into the physical world. The most dramatic manifestation of G‑dly presence happens with the introduction of another Divine soul into the world.  This is particularly so when the new soul will be raised to serve G‑d and carry the parents’ legacy into the future. Not being able to continue contributing to the world through one’s heirs is especially painful for the righteous.   They feel that it would diminish G‑d’s presence in the world.
Third, the Talmud (Yevamos 62a) states that Moshiach’s coming depends on having all G‑dly souls descend into this world. The birth of every child thus brings the world closer to Redemption, when G‑d’s glory will fill the world. To the righteous, having children is viewed as bringing the world one step closer to Redemption.
For these and other spiritual reasons a tzadik craves for nothing more than for children. And it is the only physical thing for which a tzadik will pray. Thus, by denying the Matriarch Rachel the ability to bear children G‑d guaranteed that His delight in the prayers of the Righteous would be served.
Why was Rachel’s Prayer Unanswered?
We can now approach understanding Rachel’s demand of her husband to give her children.
Rachel obviously had already prayed for children but to no avail. Rachel did some soul-searching and concluded that she was less righteous than her sister Leah.  She began to fear that her desire for children was not based on idealistic and spiritual reasons but on personal gain instead.  Perceiving a shortcoming in her prayers, she turned to her husband to pray for her.
Jacob responded that since she was the barren one, G‑d craved her prayer and wanted her to be more persistent. Obviously, Jacob would and probably did pray for her. But G‑d primarily wanted to hear her prayer.
This explains the linkage between her envy of Leah’s righteousness and her own desire for children. She plead with her husband to get her with child as she considered that her prayers had failed on account of her lack of righteousness. If she had believed that she were sufficiently righteous, she would have continued praying.
This analysis also answers Ramban’s question about why Jacob couldn’t pray for Rachel. The answer is that he certainly did but he understood that it was her prayer that G‑d craved and would ultimately bring about the desired result.
Shattering Barriers
A question still remains:
Why was Jacob so harsh to Rachel? 
The answer can perhaps be found in a story told of the fifth Lubavitcher Rebbe, Rabbi Sholom Dovber (known as the “Rebbe Rashab”).  A young man came to him with a serious spiritual problem but the Rebbe told him that he could not help him. The man was devastated, left the room, sat down and wept bitterly. The Rebbe Rashab’s older brother, Rabbi Zalman Aharon, asked the man why he was crying.  The man replied that the Rebbe had refused to help him.  Upon hearing this, Rabbi Zalman Aharon “reprimanded” his younger brother and demanded to know why he didn’t help the man. The Rebbe Rashab agreed to change his mind and proceeded to guide the sufferer and relieve him of his problem.
The question was asked, why did the Rebbe Rashab cause this man so much pain when he did, in fact, end up helping him?
The Rebbe answered that the Rebbe Rashab realized that this person had a major spiritual barrier and was not ready to be helped. His only recourse was to try and break through the young man’s shell by telling him that he was beyond help. When the young man realized that his situation was helpless, he was humbled to the core and the obstacle and resistance to the Rebbe Rashab’s counsel was broken down. It was not until then that he could be receptive to the Rebbe’s guidance.
Many of our prayers are waiting for an answer and there are many blessings waiting to be bestowed upon us. The problem is that we may not be ready to receive those answers or blessings.  We each carry with us impediments that encrust and envelop us. In these extreme cases, hearing harsh words of reprimand by an authority figure may be our last hope for receiving the blessings and having our prayers heard.
This may be the reason Jacob got angry at Rachel, despite his personification of the trait of compassion. His anger was aimed at shattering what he thought might be the obstacle to having her prayers answered. Jacob’s anger was a form of “emotional surgery” to remove the impediment to her prayers for children.
Unconventional Prayers for Unconventional Results
We must still try to understand why G‑d had not answered her prayers. It is hard to imagine that her desire for children was selfish or materialistic and that she, holiest of women, would possess such a strong stumbling block to her prayers.
The answer lies in the nature of the desired result. Rachel’s child was no ordinary child even in comparison to the other sons of Jacob. Her first son, Joseph, would carry the legacy of the Patriarchs to future generations.  Whatever spiritual energy and light Jacob and his forebears had introduced into the world depended on Joseph to transmit it. Moreover, Joseph, and only Joseph, had the power to take the lofty ideals of the Patriarchs and apply them even to the most materialistic and depraved society of Egypt.
When Joseph was born, Rachel named him Joseph saying: “May G‑d add (Yoseph) another son for me.” The Tzemach Tzedek (the third Lubavitcher Rebbe) translates this in a novel way: “May G‑d add [so that] the other should be a son for me.” Joseph was able to take even an “other,” an “outsider,” and transform him into an “insider.”  
It required a powerful and dynamic prayer for Rachel to bring this powerful and dynamic soul into the world. Her earlier prayers were certainly sincere and altruistic. But for the unconventional soul of Joseph, with its unparalleled spiritual prowess, to emerge she had to break through additional obstacles. Jacob sensed this and therefore displayed his “anger” to break the final barrier to her ability to conceive Joseph.
No More Suffering!
Our Sages (Talmud, Sanhedrin 98b) have foretold that before the Messianic Age, the Jewish people will go through the “birth pangs of Moshiach.” To bring on the unconventional power of Moshiach, who will transform the “outsiders” into “insiders,” we have had to endure unprecedented travail. We must have certainly filled and even exceeded our quota of suffering by now. To hasten and prepare for the Yoseph-unconventional increases of G‑dly light of the final Redemption, we do not need more suffering and pain. Instead, let the suffering of the past impel us to cry out to G‑d, “Ad Masai, How much longer!” even as we pave the way for Moshiach’s efforts at transforming “outsiders” into “insiders.”  Let us prepare ourselves, our families, our communities and the rest of society to welcome Moshiach by recognizing our/their insider status as G‑d’s children, who joyously serve G‑d with love!