In Spinozism, the concept of a personal relationship with God comes from the position that one is a part of an infinite interdependent "organism". Spinoza taught that everything is but a wave in an endless ocean, and that what happens to one wave will affect other waves. Thus Spinozism teaches a form of karma and supports this as a basis for morality.
Additionally, a core doctrine of Spinozism is that the universe is essentially deterministic. All that happens or will happen could not have unfolded in any other way. Spinozism is closely related to the Hindu doctrines of Samkhya and Yoga.
Spinoza's doctrine was considered radical at the time he published and he was widely seen as the most infamous atheist-heretic of Europe. His philosophy was part of the philosophic debate in Europe during the Enlightenment, along with Cartesianism.