Is Consentual Sex A Sin Against Human Or A Sin Against Allah?
The means or ways that lead to a crime or sin are also forbidden as sadd e zarya, preemptive measures. Therefore zina before marriage is forbidden for the same reason.
Dr. Irfan sahb: respectfully and humbly, I strongly disagree that sexual relations of unmarried people are forbidden as “sad e Zaria”. It is directly harmful to society and rights of others. So it is a big sin in itself – being a crime against fabric of human society. One may call it an act of utter rebellion against Allah’s design for human life i.e. social structures based on family as a fundamental unit.