Valiant for Truth - Law and Gospel

Although often identified as a Lutheran distinctive, the law-gospel distinction has been recognized by the Reformed tradition as well. Reformed theologians such as Louis Berkhof have spoken of the Bible as containing two parts–the law and the gospel. 

Now it is evident that no one is justified before God by the law, for ‘The righteous shall live by faith.’ But the law is not of faith, rather ‘The one who does them shall live by them.'

The law teaches us what is to be done; the gospel (if it is taken to represent the grace of the Holy Ghost) differs from the law because it gives strength to do it

Now, the law is a doctrine partly known by nature, teaching us that there is a God, and what God is, and what he requires us to do, binding all reasonable creatures to perfect obedience both internal and external, promising the favor of God, and everlasting life to all those who yield perfect obedience thereunto, and denouncing the curse of God and everlasting damnation to all those who are not perfectly correspondent thereunto.