The Sin of Wasting Male Semen
Because of their acceptance of the established doctrine of the 'male' seed, the Fathers of the Church and medieval theologians were horrified by the idea that such precious seed could be 'wasted'.
"Because of its divine institution for the propagation of man, the seed is not to be vainly ejaculated, nor is it to be damaged, nor is it to be wasted."
Clement of Alexandria (191 AD), The Instructor of Children 2:10:91:2.
This led to the Church's condemnation of