When safeguarding justification led to unjustifiable error

The gospel suffers at the hands of its friends and not just its enemies. With the best of motives, as far as we are able to read them, attempts to safeguard doctrines from perceived error can have the effect of producing further, if opposite, errors. And so it has proved to be with the doctrine of justification by faith alone. It is open to abuse, no question about that, but the danger of abuse can produce a safer version that eclipses the glory of God's free grace in the gospel.

Here is J. I. Packer on Richard Baxter's innovative improvement on justification:

Baxter's view sprang from natural theology; he thought Bible teaching about God's kingdom and rule should be assimilated to contemporary political ideas, or, as he put it, that theology should follow a 'political method'...Our salvation requires a double righteousness: Christ's, which led to the enacting of God's new law, and our own, in obeying that new law by genuine faith and repentance. Faith is imputed for righteousness because it is real obedience to the gospel, which is God's new law.

Packer notes that in putting forward this view Baxter was seeking to avoid a perceived error connected with the Reformed view of the imputation of Christ's righteousness to the believer:

Baxter was convinced that those who held the ground and formal cause of our justification to be the imputing to us of Christ's own righteousness (i.e. his fulfilment of the precept and penalty of the moral law) were logically committed to Antinominianism, on the 'payment-God-cannot-twice-demand' principle.

At this point in his thinking (though not elsewhere) Baxter assumed, with his Roman and Socinian contemporaries, that law-keeping has no relevance for God or man save as a work done to earn acceptance and salvation, so that if the law has been kept once in our name no basis remains for requiring us to keep it a second time in our own persons. It is an odd mistake to find him making; but he never got this streak of legalism out of his theological system.

Knowing that theological ideas have pastoral consequences Packer then goes on to say that:

The scheme is so artificial as to be spiritually unreal; for a sinner pressed in conscience by the burden of uncleanness and guilt finds relief, not by reminding himself that is faith is evangelical righteousness according to the new law, but by looking to the cross of Christ. 'My Saviour's obedience and blood/Hides all my transgressions from view.' Talk of one's faith as one's righteouness at such a time is at best a frivolity and at worst a snare.

Baxter's approach was methodologically flawed, rationalistic and 'theologically vicious.' It had 'bad effects all along the line.' But if only these bad effects were limited to one generation. That was not to be the case. Packer's solemn observation on the impact of error across time is worth reflecting on:

Thus Baxter, by the initial rationalism of his 'political method,' which forced Scripture into an a priori mould, actually sowed the seeds of moralism with regard to sin, Arianism with regard to Christ, legalism with regard to faith and salvation, and liberalism with regard to God. In his own teaching, steeped as it was in the older affectionate 'practical' Puritan tradition, these seeds lay largely dormant, but later Presbyterianism in both England and Scotland reaped the bitter crop.

It is sadly fitting that the Richard Baxter Church in Kidderminster today should be--Unitarian. What we see in Baxter is an early stage in the decline, not simply of the doctrine of justification among the Puritans, but of the Puritan insight into the nature of Christianity as a whole.

J. I. Packer, Among God's Giants (UK)/A Quest For Godliness (US): The Puritan Vision of the Christian Life, p. 207-8, 209-10