I found this quite interesting in Ben Witherington’s book The Problem with Evangelical Theology.
“It has even been said that he [John Wesley] wed a Protestant theology of justification with a Catholic theology of sanctification and ethics. There is some truth in this claim.” (172)
“Even though Paul certainly believes that salvation is by grace through faith, he is also quite clear that certain forms of behavior by believers can make one unworthy of God’s dominion. This is an important point often overlooked in the study of the Pauline corpus, but is has not been overlooked in Wesley’s treatment of this matter. It was, of course, Wesley’s view that initial justification was by grace through faith, but final justification and entrance into God’s dominion was on the basis of faith plus deeds of piety and charity. Texts such as those just listed were important for Wesley when he wanted to stress that the conduct of Christians could affect their final destiny. Of course, a text such as Matthew 5:20 would also be cited by Wesley where Jesus suggests the same thing. Unless one’s righteousness exceeds that of the scribes and Pharisees, the dominion cannot be entered. Nor would Wesley put up with either quietism (one need do nothing, God will simply do it all through the internal workings of the Spirit) or with the notion that while one must do good works to please God, for the good tree will bear such fruit, in the end such works are either incidental or superfluous to one’s being saved. Wesley took seriously the three different ways salvation is spoken of in the NT (I have been saved, I am being saved, I shall be saved to the uttermost), and he believed that our behavior, at least in a negative way, could affect the final outcome if we are talking about final justification, final sanctification, final entrance into the dominion.” (177)