Likutei Moharan 250:4/ליקוטי מוהר"ן ר״נ:ד׳

14. Prayer is the aspect of Providence, <the aspect of> transcending nature; for the natural course dictates a certain thing, and prayer changes nature’s course. This is the aspect of greatness, the aspect of “For what nation is so great that they have God so close to it, as God our Lord is, whenever we call upon Him?” (Deuteronomy 4:7). This is our greatness, that God hears our prayers and changes the natural order by means of His Divine Providence. As it is written (2 Kings 8:4), “Tell me, please, of the great things Elisha has done”; and as our Sages, of blessed memory said: That which Elisha accomplished, he accomplished through prayer (Megillah 27a). Thus it is that prayer, which is the aspect of miracles and Providence, is the antithesis of nature—this is the aspect of greatness.