The verse states:1 "In days to come, Yaakov shall take root, Yisroel shall blossom and bud, and the face of the world shall be filled with produce."
The verse refers to the time of exile.2 Though planting is on the level of "Yaakov," growth is on the level of "Yisroel." As we know,3 Yaakov and Yisroel allude to two spiritual levels. Yaakov is "yud eikev" [eikev in Hebrew means heel], and is at a lower spiritual level. Yisroel is the lofty level of "li rosh" " to me a head." Through spiritual service during times of exile, we ascend from the level of Yaakov to that of Yisroel.
Exile is known as a time of slumber.4 When a person sleeps, he dreams, and during a dream it is possible for totally contradictory matters to unite.5 So too concerning exile.
A mainstay of spiritual service during exile is the proper recitation of the Shema. When one says the words: "Hear O Israel, the L-rd is our G-d, the L-rd is One,"6 he should ponder their meaning. He should understand the phrase to mean that the four "corners" of the world, the seven "heavens" and the earth; are totally nullified to the "aleph" the Infinite One, Master of the world.7
Yet exile affects a person in such a manner that soon after this lofty contemplation, all sorts of stray thoughts enter his mind. It is as if G-d's unity was never pondered. This is particularly true when, after prayers, a person becomes involved in worldly affairs. He then tends to forget that which he pondered at the time he recited the Shema. Quite frequently, the person becomes enmeshed in pride, and completely forgets about G-dliness.
All the above comes about because the state of exile is like a dream, in which opposites can unite.
This is the meaning of the phrase "Though I slumber, my heart is awake." Though in exile I may find myself in a state of slumber, still my heart is awake to mesirus nefesh. For in times of exile it is easier to awaken within oneself the power of mesirus nefesh than it was while the Temples stood.
The latter part of the verse, "my heart is awake," refers to the heart's essence, where the core of one's Judaism is found. This essence exists constantly, even in times of exile, and is revealed through an opponent. Opponents of Torah and mitzvos awaken the heart's essence, and the essence of Judaism. This essence reveals itself in a Jew's simple and complete faith in G-d, and his actual mesirus nefesh.
Herein lies the additional merit of the simple and unlettered Jew. The simple Jew surpasses even the scholar, in that he possesses a greater degree of mesirus nefesh and sincerity. Simple Jews take part in congregational prayers, utter Psalms and believe in the coming of Moshiach. They do all this with the heartfelt sincerity brought about by simple and complete faith in G-d.
Jews say: "My state of slumber is too great for me to ponder the end of exile. However, my heart is awake to the Redemption." And those Jews who think and speak about Moshiach will merit to greet him.
In summary: "Yaakov" refers to people who are simple but sincere, while "Yisroel" refers to scholars. Exile, with its internal contradictions, is likened to a dream. But it is specifically during this "dream state" that the power of mesirus nefesh regarding Torah and mitzvos becomes strengthened. Jews who speak of Moshiach and prepare themselves for his coming through repentance and good deeds will merit to greet him.