ויֹּאמֶר משֶׁה אֶל הָעָם אַל תִּירָאוּ כִּי לְבַעֲבוּר נַסּוֹת אֶתְכֶם בָּא הָאֱלֹהִים וּבַעֲבוּר תִּהְיֶה יִרְאָתוֹ עַל פְּנֵיכֶם לְבִלְתִּי תֶחֱטָאוּ
What does the 8th word in the verse mean? Generally, בעבור means "in order to" or "for the sake of," as it is used in the second clause of this verse (without the prefixed ל). Adding the ל seems to make it a difficult word to understand. "For in order to"?
What does the ל in this word mean, and how does it change the meaning of the word? And if it doesn't change the meaning of the word, why is it necessary?
And why the difference between the first and second time it is used in the verse?