The story in the portion Toldot is a well-known one: Isaac wants to give the blessing of the first born to Esau, the selfish son, but Rebecca tells Jacob they have to trick Isaac into giving him the blessing instead, doing so through preparing food and putting on Esau’s clothing. And the Midrash gives us an interesting insight into Jacob’s psyche and emotions during these moments that are important for us to understand.
The Midrash tells us that Jacob does not want to do this, and that he is forced to. It says that as he’s getting prepared to enter his father’s room, he is bent over, completely broken, and crying. So, as Jacob is getting ready to receive what is probably the greatest Light revealed in this world, how does he go into it? Forced, bent over, completely broken, and crying. When he enters the room, his father senses something's wrong for many reasons; Isaac smells the Garden of Eden, yet knows that Esau is not connected to the Garden of Eden, and he hears Jacob use the names referring to the Creator, yet knows Esau is not connected to the Light of the Creator. Therefore, he tells Jacob, “I want to feel you. I want to see if you're really my son Esau.”
Jacob is crying so much that the tears are falling on his hips and thighs, and it says his heart is as weak as wax. He's so upset and broken that he can't even move, so the Creator sends two angels to support him and take him close to Isaac, since he is not going on his own. Jacob has lost power over his body, and these two angels are holding him; that is the secret of the verse in Isaiah - “Do not give up, because the Creator is there to support you.”
But, why is the Creator doing all this? Poor Jacob - aren't there easier ways for him to draw all this Light? The answer, and this is vital to understand, is that the only way for Jacob to merit the great gifts from Isaac is if he is completely broken. Only when Jacob felt nothing of himself, no thoughts, merit, or ability of himself, could the blessings come. The only way Jacob, or anyone, can awaken that great Light and draw down those blessings is to be as empty as he was in that moment.
Until the End of the Correction, the end of pain, suffering, and death in this world, all the Light of elevation and revelation comes from this moment in Jacob's time. And only because Jacob was so lacking and empty was he able to draw that Light down for himself, and the world. We learn from this, therefore, something extremely important: if we want to have great Light and draw down the highest blessings, we have to feel devoid of merit, like Jacob did. We have to have, as the Midrash tells us, a heart as weak as wax, such that we are so empty we can’t even move and need the angels to support us.