At the time of the Messiah (the correction of humanity), evil increases and impudence and vice will be led by the heads of the mixed multitude (Erev Rav). Then the Hidden Light will appear from the Heaven – The Book of Zohar, followed by the writings of the Holy Ari. And this learning will root out the evil in our souls. We will be rewarded with cleaving to the Upper Light, and we will be rewarded all the virtues in the world. It is for this reason that this Light appeared.
And the essence of your study will be to attain illumination and Godly liveliness in your soul. The Ari said that at that time the hidden will become revealed.
The Hall of Blessing, Deuteronomy 208
Let not the eunuch say, “For I am a dry tree, and who am I to approach the holiness within, in the books of Kabbalah?” This is because all the righteous have already agreed that today this is the counsel of the evil inclination and a lie. And although a person does not understand what he reads, still, the words of the Holy Zohar have healing power for the soul, and are approachable for every soul. Rabbi Tzvi Hirsh Horovitz of Backshwitz, Upright Guidance, Item 5.
Study of The Book of Zohar brings a miraculous force. Even if a person does not understand what he studies, it is important to the Creator and loved by Him, similar to how an infant does not understand what he speaks, but the parents rejoice at hearing his voice. Hence, one cannot complain that he does not know or understand.
Pele Yoetz, Chapter, “Zohar”.