Morality is a social construct designed to protect society and humanity from human behaviours which the society in question deems harmful to itself. A society in which cannibalism is commonplace, for example, will not consider it immoral, in the same way that the vast majority of people don't consider meat eating or slaughterhouses immoral. Think about how, in western soyciety, female genital mutilation is considered to be on the same level as murder, yet circumcision is a commonplace practice. This is an example of how morality is socially constructed.
Religion is a secondary manifestation of morality, designed as a means of controlling people who don't adhere to the regular moral code by creating a moral code which comes with "rewards" (i.e. 72 virgins in the afterlife, going to heaven, etc.).
Some may think that the law is a manifestation of morality as well, but it actually isn't. While on the surface, the goal of the law is to control the masses in the same way that it is for morality and religion, the underlying aim of the law is different. The law was created to suppress the masses to the benefit of the social elite. The secondary aim of the law is to keep citizens as productive as possible, while the primary aim of the law is to prevent the possibility of a revolution or coup d'etat.
