We at home are religious, but not too much.
We consider that masturbation is always bad, although in men it is a kind of necessary evil or rather, inevitable, and within certain levels, it must be accepted, although not promoted. It is with the girls that he must be more strict to avoid her.
They are ethical and cultural considerations so, as I already had a precedent, each one is free to share some motivation, all or none, or to be radically against it, but in the end these are our beliefs and I know that we are not the only ones to share opinion.
1- Girls must be modest, and they must know how to contain their appetites. Indulging in masturbation is a serious fault.
2- Female sexuality is deeper than that of men, it must always be linked to feeling, a quick and empty pleasure does not bring them anything, on the contrary, it distorts that deep sexuality.
3- This action will weaken the bond with your husband. The sexual bond is not the only one, but it must be important in the marriage. Obtaining pleasure, even if empty, weakens the bond with your man. Pleasure must always depend on being loved.
4-It requires time and effort that the girls must dedicate to other things.
5- Create addiction, sooner or later you will want another, and another...
6- Also in men, but more in women, it is an unpleasant, lascivious behavior.
7- Encourages lies and concealment in families and in the couple. Privacy must exist, and for us it is fundamental, but seeking it to do something prohibited is an abuse.
I have tried to systematize my ideas, it is evident that our opinion is not structured in points, it is more "customary", but I think it can be dissected like this, and it is clearer. If later I come up with more points, I add them.