Augustin Gretillat (March 16, 1837 at Fontainemelon – January 14, 1894 in Neuchâtel) was a Swiss Protestant pastor, theologian and professor of theology.

He succeeds John Calvin and Bénédict Pictet in the very short list of authors of complete treatises on dogmatic in the French language.

Considered in itself, in its motives and in its conclusions, it was the most daring challenge to reason and human conscience; an aberration of the Christian genius to which it will always be astonishing that the cause of divine truth could have survived on earth.

Augustin Gretillat, the last author close to orthodoxy who left a Systematic Theology in French, strongly affirms his Arminianism: the particular predestination is conditional, "relative to the acts of the human will"; "This human conditionality, in fact, is realized in two opposite alternatives, both precognized and not predetermined, which are designated in Scripture by the terms of faith and unbelief.

"[7]With regard to his main work in systematic theology (1885-1892), his friend, the writer Philippe Godet states: