Actually It is permissable to stimulate oneself. In the context of a licit conjucal act. In fact I’ve read reference that the wife is allowed to stimulate herself to orgasm if the husband cannot. Again in the context of a complete licit conjucal act. Infact it may even be **necessary **for the husband to stimulate himself prior to intercourse, say in the case of partial ED. If the husband should stimulate himself during foreplay and for some reason the act is interupted and not completed or there is an accidental release, no sin has been commited because the intent was toward a licit conjucal act. However because the husbands climax is tied inseperably to the procreative means, **It is never permissable to ejaculate outside of the “required vessel.” **It’s different with the wife because her climax isn’t tied inseperably to the proceative means. The procreative and unitive means can happen if no climax is achieved on her part at all. So logic would dictate that it wouldn’t matter if it took place before, during, or after. One could argue that her climax infact would in fact add rather than take away from any of these meanings. However, All intensionally derived sexual pleasure must occur in the context of a licit conjucul union. And again, every ejaculation must occur in the required vessel. You can pose an infinate number of more and more complicated sets of circumstances, but I think that if you always keep these two things in mind, the anwers become clear.
