Many people stumble and fall just as they are about to reach their final perfection. Some were already at the gates of holiness and could have easily entered completely in the realm of holiness, but retreated because obstacles and confusions arose against them with such intensity that they felt it was impossible to withstand them. The main means of rectifying this situation is Torah study. One must be very strong never to neglect Torah study, no matter what one must endure. One will then be able to overcome anything through the Torah, for all rectifications and purifications — from the first to the last — all are only through the Torah.
From Likutei Halakhot, Birkhat haMotzi 5:38.