I beg of You only one thing—please do not take the trouble to return soon.—I am ready to wait for You for all eternity.
Source, in full
On her dark night of spiritual desolation amidst devotion, in a letter addressed to Jesus, as quoted in Mother Teresa: Come Be My Light (2007) edited by Father Brian Kolodiejchuk, p. 192; regarding this quote, Fr. Kolodiejchuk writes: "...when addressing Jesus — that is, in prayer — she could express herself with ease. Fufilling her confessor's request, she sent to him a letter addressed to Jesus, enclosing it with her letter dated September 3, 1959."