Reproving Sinners as a Means of Grace.

Discourses 3 and 6 on the Sermon on the Mount list activities that Wesley considered works of mercy:

Giving alms, feeding the hungry, clothing the naked, assisting the stranger, visiting those that are sick or in prison, comforting the afflicted, instructing the ignorant, reproving the wicked,  exhorting and encouraging the well-doer.

Unlike Discourse 6, doing good to others’ bodies and souls is not explicitly designated as a means of grace in Discourse 3, however the following statement does imply that when we engage in works of mercy, God’s grace is working through us—

This power [to do good to the soul], indeed, belongeth unto God. It is He only that changes the heart, without which every other change is lighter than vanity. Nevertheless, it pleases Him who worketh all in all, to help man chiefly by man; to convey his own power, and blessing, and love, through one man to another.

Wesley’s Notes for Ephesians 5:13 also implicitly identify reproving sin as a means of grace. Paul’s statement is intriguing—
τὰ δὲ πάντα ἐλεγχόμενα ὑπὸ τοῦ φωτὸς φανεροῦται,              
            all        exposed     by           light     is lit up  
πᾶν γὰρ τὸ φανερούμενον φῶς ἐστιν    
all            that lights up         light     is
 
(John 3: 20 and 21 contain similar themes of exposure by an illuminating light.  In the case of the gospel, Jesus is identified as the light that can expose the nature of human deeds.)

In Wesley’s opinion when Christians reprove sin, heavenly light is working through them.  This is not an explicit biblical precedent for Wesley’s claim that reproving sin is a means of grace, but it comes close.