The Jewish King Chizkiyahu fell critically ill, as recorded in the second Book of Kings, chapter 20. The prophet Isaiah visited Chizkiyahu and informed him that the sickness was a punishment for Chizkiyahu's refusal to have children. Chizkiyahu explained that he'd prophetically seen that an evil person would descend from him, and that's why he hesitated to have children. Isaiah countered: "You have a mitzvah to have children -- let God worry about the rest." Chizkiyahu prayed for forgiveness and God granted him another 15 years of life. The episode illustrates a foundation of Jewish thought: It is up to us to make the appropriate effort, while the result are in God's hands.