I have endeavoured to describe the true, the scriptural, experimental religion, so as to omit nothing which is a real part thereof, and to add nothing thereto which is not. And herein it is more especially my desire, First to guard those who are just setting their faces toward heave, from formality, from mere outside religion, which has almost driven heart-religion out of the world; and, Secondly, to warn those who know the religion of the heart, the faith which works by love, lest at any time they make void the law through faith, and so fall back into the snare of the devil.

—Preface to the Sermons 5.4

If you are having trouble translating 18th century English, let me help. Here Wesley’s focus is on the Prize—life forever with God, or what we call “heaven.” He indicates this should be the first priority of any Christian and is available to us, not by going through the motions, but by developing an ongoing relationship with the living God, a relationship that will inevitably (but sometimes imperceptibly) change us into his very image. It’s a free gift but we can lose it if we use our freedom in Christ as license to sin. God is holy and calls us to be likewise. This comes through faith made manifest in joyful obedience to the Christ who loved us and claimed us.