The Patimokkha rules can be seen as promoting three things; social cohesion of the Sangha - both with the group(s) that follow the vinaya, or their relationship with other vinaya & non vinaya disciples; a means to curb bad habits and impulses of members, and as a reminder of what is conductive for enlightenment. Whether these came about in the Buddhas time, or after is not worth much time debating here, so long as these fulfil the task of being a reliable Employees Handbook of Sakyaputta Corp! as a friend has called it. So the rules below are solely for a mendicants, but for a lay person there is advice that can be distilled also.
The five trades which a lay person should not engage in is Trade in weapons, trade in human beings, trade in flesh, trade in spirits [intoxicants] and trade in poison.1 These are not to be engaged in as they go against the precepts, or aim away from the underlying intention the precepts aim to promote in some way.
The Buddha said "Not by birth is one an outcast; not by birth is one a brahman. By deed one becomes an outcast, by deed one becomes a brahman."2 and this is true of everything we intentionally do, as it says in the first & second Dhammapada Verses“Mind precedes all phenomena, created by the mind which rules it.” These point to the skillfulness of our action, being the thrust behind the outcome. As the first & second verses continue 1- “If the mind is corrupted, and one speak or act, from there stress comes, like a wheel of a cart follows the track of an ox that pulls it.” 2 - “If the mind is pure, and one speak or act, from there pleasure comes, like a shadow that does not leave.”
As people living in the worldly life, we still have responsibilities, and things we need to take care of, so there is no point looking around for distractions, but to look for means to train our mind, thinking and intentions as we have a responsibility, that of a lay people still living in the world and the selection of rules may assist us in aiming in the right direction.
At the end of the day I may be right, I may be wrong, but I share this hoping I am one, the other, both, or neither.
MN 117 defines wrong livelihood as scheming, persuading, hinting, belittling, and pursuing gain with gain.
Deliberately lying to another person that one has attained a superior human state is a parajika offense. (Pr 4)
Acting as a go-between to arrange a marriage, an affair, or a date between a man and a woman not married to each other is a saºghadisesa offense. (Sg 5)
Engaging in trade with anyone except one's co-religionists is a nissaggiya pacittiya offense. (NP 20)
Persuading a donor to give a gift to oneself, knowing that he or she had planned to give it to a Community, is a nissaggiya pacittiya offense. (NP 30)
Telling an unordained person of one's actual superior human attainments is a pacittiya offense. (Pc 8)