Full Idea
Jacobi argues that Spinoza's pantheistic belief that nature and God are the same thing is really equivalent to atheism, and the fatalist implications of his deterministic system was deemed incompatible with genuine freedom and moral responsibility.
Gist of Idea
Jacobi said Spinoza's pantheism is atheism, and his determinism destroys morality
Source
report of Friedrich Jacobi (Letters on the Teaching of Spinoza [1785]) by David West - Continental Philosophy: an introduction 2 'Critics'
A Reaction
Spinoza would only be atheistic if he reduces God to nature, rather than raising nature to God. European philosophy is dominated by this (false!) idea that responsibility needs perfect free will.
Book Reference
West,David: 'Continental Philosophy (2nd ed)' [Polity 2010], p.33