Baal HaSulam, “Introduction to the Study of the Ten Sefirot,” Item 133: It is rather like a king who wished to select for himself the most loyal of his subjects in the country and bring them in to work inside his palace. What did he do? He issued a decree that anyone who wished, young or old, would come to his palace to engage in the work inside his palace.
However, he appointed many of his servants to guard the palace gate and all the roads leading to it, and ordered them to cunningly deflect all those nearing his palace and divert them from the way that leads to the palace…
And only the heroes among them, whose patience endured, defeated the guards and opened the gate. And they were instantly awarded seeing the King’s face, who appointed each of them in his right place.
The guards are appointed in order to guard a person. He mustn’t come near the King’s palace and pass the place where the guards stand, unless he establishes an inner guard.
The Creator has many policemen and they are on each of the 125 degrees, preventing a person from coming nearer. They show you that you are allowed to rise only to a specific level, and you are not allowed to pass above that for the time being. It is because they see that you are not ready for the upper level yet. This is what happens each time.
The guards make sure that a person will not advance any further (although it is impossible, since there are rigid laws of conformity in the spiritual world). The guards reveal deficiencies to a person—a place for self-checking. They evoke him and don’t let him relax in his current state by bringing him all kinds of troubles.
They guard the person; the Light and the Creator don’t need to be guarded because it is impossible to harm them if you are not worthy of seeing them. It is all done according to the equivalence of form; if I am not suitable for a higher level, I don’t recognize it.
What does it mean that I cannot advance? Do I see that the road before me is blocked? If I haven’t corrected myself yet on the previous level, I cannot advance and climb the mountain a few meters further, but the guards help me and point me at the problematic point. They are there in order to protect me, to hasten me, to bring me closer, and to help me reach the necessary discernments. Everything is in a person’s favor and for his correction.
From the 1st part of the Daily Kabbalah Lesson 1/2/13, “The Introduction to the Study of the Ten Sefirot”