This sentence tells us a "moderate" truth, tells us how to love children, how to be strict with children, that is, how to love children and how to be strict with children.

Love is not doting, not doting, but loving for the healthy growth of children.

Strict, what aspects should be strict, how to be strict, to what extent, and what is the purpose of strictness. There should be a clear grasp and understanding here, which is the meaning of "case".

The purpose is for the healthy growth and progress of children.