I am reading George Marsden's excellent biography on Jonathan Edwards. He spends some time talking about the Puritan upbringing of Edwards.
How different from our day - what modern parenting book has this design - "to teach children to recognize how insecure their lives [are]"?
Much of Puritan upbringing was designed to teach children to recognize how insecure their lives were. Every child knew of brothers, sisters, cousins, or friends who had suddenly died. Cotton Mather, under whose preaching Timothy had once sat, eventually lost thirteen of his fifteen children. Parents nightly reminded their children that sleep was a type of death that taught them such prayers as “This day is past; but tell me who can say / That I shall surely live another day.” The New England Primer illustrated the letter “T” with “Time cuts down all, both great and small” and a woodcut of the grim reaper. “Y” was “Youth forward slips, Death soonest nips” with a woodcut of Death holding a large arrow at a child’s head. One of the Edwards children's surviving writing exercises reads, “Nothing is more certain than death. Take no delay in the great work of preparing for death."
If life was uncertain and frightening, eternity was more so. Parents who themselves experienced God's saving grace and who lost children in infancy might have hopes in God's covenant promises of mercy from generation to generation. Young children might have saving grace, even if they did not live long enough for it to come to fruition in identifiable signs of conversion. One nighttime prayer (a form of which has long survived) was "Lord, if my Soul this night away thou take, / Let me by morning then in Heav'n awake." Yet no child was innocent or worthy of anything but eternal damnation. All were totally depraved. Not only would they sin as soon as they could, but they were also born guilty of the sins of the race. "In Adam's fall, we sinned all," was the first lesson in the New England Primer. Children soon learned that in their natural state they deserved the flames of hell. Only God's mysterious grace might rescue them. (Marsden, Jonathan Edwards: A Life, pp. 26-27)