My children go to state schools on weekdays and get their religion at Sunday schools on Sundays. And they are a credit to me.

The Catholic Answers

Whilst your children may be outwardly all that you wish them to be, can you read their souls? Christianity is essentially an interior and spiritual religion. Interior virtue is not regarded highly when religion and morality are excluded from week-day education. The mere fact that religion is excluded from the weekday curriculum and taught on one day whilst secular subjects are taught on several days tends to make religion seem a side-line of much less importance. And the logical consequence is that many regard religion, if they bother about it at all, as a matter for Sundays, and not as having any particular reference to week-days. Sunday school training is not enough.

Radio Replies Volume 1 by Rev. Dr. Leslie Rumble MSC and Rev. Charles Mortimer Carty