by God, practices whose energy and issue and not intrinsic but derived from the Spirit whom Owen calls their ‘great efficient’ or ‘great sovereign cause’.27 These practices are duties for whose fulfilment only the divine Spirit is sufficient. ‘All other ways of mortification are vain, all helps leave us helpless; it must be done by the Spirit … Mortification from a self-strength, carried on by ways of self-invention, unto the end of a self-righteousness, is the soul and substance of all false religion