Some 18th century Protestants taught and sang of freedom from a legalistic clinging-on to O.T. law-keeping, why did they feel the need to do that?

Given various quotes and hymns from the mid 1700s onward, it seems some Reformed Protestants were showing how the Old Testament law only served to make it impossible to find the liberation that the gospel of Christ brings. From then, even till today, a popular claim in many Reformed Protestant circles is that the Law of Moses is the believers’ ‘rule of life’ – meaning the Ten Commandments which have the moral essence. One example of such a claim was a sermon preached on behalf of the Evangelical Association on 16th August, 1787 at a chapel in Artillery Lane. There it was stated from the pulpit that, *“The moral law is the foundation of all religion, both moral and divine.”* To substantiate it, the way Moses struck the rock so that water gushed out, was paralleled with Christians ‘smiting the law’ by keeping it, to get refreshing comforts from doing that. Another preacher of the time wrote at length about such claims. One instance was where he said, “A friend of mine once asked a certain divine in London what he thought of the law as the believer’s only rule of life. He replied, *"The believer must look with one eye to Christ, and with the other to the law."* (The author’s friend said to the divine that, then, every believer must be cross-eyed!) *Law and Grace Contrasted* William Huntington – Addresses, p.125, edited and abridged version published in 1999 **Was there something of a battle going on between two groups of Reformed Protestants on the matter of Mosaic law-keeping, and if so, why?**