Adam Clarke on Psalms 116:6

The Lord preserved the simple - פתאים pethaim, which all the Versions render little ones. Those who are meek and lowly of heart, who feel the spirit of little children, these he preserves, as he does little children; and he mentions this circumstance, because the Lord has a peculiar regard for these young ones, and gives his angels charge concerning them. Were it otherwise, children are exposed to so many dangers and deaths, that most of them would fall victims to accidents in their infancy.