Question: How does prayer help build a screen if we do not ask for it directly or we do not explicitly say in the prayer: “We ask to build a screen”?

Answer: You are asking for it because you are praying for someone else. By doing this, you build the screen.

Asking for someone else is the most reliable way to change yourself and your position regarding the entire Kli.
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From the Daily Kabbalah Lesson 8/11/24, Writings of Rabash “Laboring and Finding”

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