In American Colonial churches, they used the idea of the scary mask to teach people not to be afraid of anything on the earth, especially children, so that when it came their turn to die, they would not be afraid of death, even. This was important from the time people arrived on ships due to the abysmal average age of death:
In 1607, the ship Susan Constant discharged l05 passengers; six months later, two-thirds were dead.
Between l607 and l624, 6,000-10,000 colonists arrived; but only l,275 remained alive.
It's starting to rain here, so I'll leave the death rate tables to your perusal because my computer goes down when full rains starts.
It was deemed very important that the colonists faced things as bravely as possible, considering how poor their odds of survival were after the first two boats left their human cargo and went back to get more.