Musar do Rut 4:17

But if we reflect further, we see the greatness of the goodness of the Holy One Blessed be He, that the punishment itself results in great good. For a place was prepared for her to restore her tranquility and to sustain her old age. For in the death of the wife of Boaz, it was ordained by Heaven that he marry Ruth, as it is written (Mishlei 19:14): "And from the L-rd, an understanding wife." And through this Oved was born to her, who, as it is known, was Machlon, as the Kabbalists wrote, wherefore it is written (Ruth 4:17): "A son was born to Na'ami" [(and not "to Ruth," Machlon having been the son of Na'ami [viz. Ibid. 1:2])]. In sum, a man must believe that "from the mouth of the Almighty evil does not emerge, and if suffering does result we must know that good lies in it.