afaik that example given by Lord Jesus Christ was advising Christians to adopt a kind of behavior that resembles well behaved unspoiled children, like the ones present at highly religious families who made sure they and their offspring were behaving in exemplary ways regarding their religious injunctions, residing at places which He frequented - such people, along with saintly persons, are prime candidates for entering Heaven or more generally the Kingdom of GodQuote:
Originally Posted by anon
a child is often considered as being innocent upon entering this life and this particular body (incarnation), it didn't have time to develop attachments to the materialistic world in this life, which are formed while living and strengthened especially when living in frivolous, immoral ways, unrestrained by religious injunctions - religious rituals are designed to cleanse a person from these attachments, preparing new prime candidates as mentioned above
however, the very reason for incarnating in a body is due to developed attachments from previous lives, so a child is not free (or innocent) from reactions due to their past life actions - in other words, the way you are living this life will determine where you end up in your next life - usually, a child entering this life still didn't attain the level of a prime candidate, but it was worthy of entering a human body or better yet, entering a highly religious family where it may have excellent conditions to further advance spiritually and reach the level of a prime candidate