This is the marrow of what has been called Neonomianism - William Rushton

The last error I shall charge upon Mr. Fuller’s principles is one which is not openly avowed in his writings, but which follows as a deduction from his general sentiments: namely, that not the obedience of Christ, but the act of believing, is imputed to us for righteousness. This is, in short, neither more nor less than a revival of the Neonomian error, which error consists principally in the following doctrine; viz., "That Christ, having satisfied for the breach of the old law of works, hath procured and given a new law, a remedial law, which is the gospel, containing precepts, promises and threatening, and which saith, DO AND LIVE, in some milder sense than the first covenant. That faith in Christ is the principal part of that obedience which is required by the new law, and this is accepted for righteousness, instead of that perfect unceasing obedience, which the law of ten commands requires." [See the preface to Beart’s Eternal Law, &c.] This is the marrow of what has been called Neonomianism; which doctrine, as to substance, is taught in the writings of Mr. Baxter, of the Arminians, and of the most learned of the Roman Catholics.