Verse 3. You shall not mix or imbibe any false doctrine with these holy states; in them you shall receive pure good from heaven unmixed with evil, and regard it as most holy, even though it seem distasteful to the natural man; for deliverance from the unregenerate condition is thus rendered complete and thorough: and by this means the deliverance by the Lord from the unregenerate condition will be kept in view by the regenerate in all their alternating states.

In most cases, the meaning of "before" is pretty straightforward, both as a way of assessing relative time, and in its use meaning "in someone's presence." It takes on a deeper significance, though, when used in connection with the Lord. To be "before" the Lord means not just in His presence, but also receiving the desire for good and the understanding of truth from Him, and living according to them. And when used as an assessment of time in connection with the Lord, "before" means "from eternity," and refers to a spiritual state rather than time as we experience it.

(References: Apocalypse Revealed 366, 617; Arcana Coelestia 6983, 8439, 9888)