Ninth Direction. Be sure to improve the covenant of grace for thy assistance in thy holy course. Moses himself had his holiness not from the law, but gospel. Those heroic acts, for which he is recorded as one so eminently holy, they all are attributed to his faith, Heb. 11:24, 25. ‘By faith’ Moses did this, and ‘by faith’ that, to show from whence he had his strength. Now the better to improve the covenant of grace, for this purpose, consider these three particulars.
First. That God in the covenant of grace hath promised to furnish and enable his children for a holy life, ‘I will put my spirit within you, and cause you to walk in my statutes,’ Eze. 36:27. This is the way God hath by himself. The mother can take her child by the hand to lead it, but cannot put strength into its feeble joints to make him go. The prince can give his captains a commission to fight, but not courage to fight. There is a power goes with the promises; hence it is they are called ‘exceeding great and precious promises,’ because given for this very end—that by them we 'might partake of the divine nature,’ II Peter 1:4; and therefore we are not only pressed to holiness from the command, but especially from the promise, ‘Having therefore these promises,’ (he means to help and encourage us), ‘let us cleanse ourselves from all filthiness of the flesh and spirit, perfecting holiness in the fear of God,’ II Cor. 7:1. O it is good travelling in his company that promiseth to pay our charges all the way—it is good working for him that promiseth to work all our work for us, Php. 2:12, 13.
Second. That God hath laid up in Christ a rich and full treasure of grace to supply thy wants continually, ‘It pleased the Father that in him should all fulness dwell,’ Col. 1:19. Fulness! all fulness! all fulness dwelling! not the fulness of a land-flood, up and down; not the fulness of a vessel, to serve his own turn only; but of a fountain that lends its streams to others without straitening or lessening its own store. Indeed, it is a fulness purposely ministerial, as the sun hath not its light for itself, but for the lower world, called therefore :/: (shemesh),because it is the great minister and servant to hold forth light to the world. Thus Christ is the Sun of righteousness, diffusing his grace into the bosoms of his people. ‘Grace’ is said to be ‘poured into his lips,’ to let us know he hath it, not to keep to himself, but to impart, ‘that of his fulness we may receive, and grace for grace.’ And,
Third. That every child of God hath not only a right to this fulness in Christ, but an inward principle —which is faith—whereby he is, by the instinct of the new creature, taught to suck and draw grace from Christ, as the child doth nourishment in the womb by the navel-string from the mother. Therefore, poor soul, if thou wouldst be more holy, believe more, suck more from Christ. Holy David, affected with the thoughts of God’s gracious providence in delivering him out of his deeper distress, takes up, as the best messenger he could send his thanks to heaven by, a strong resolution for a holy life, ‘I will walk before the Lord in the land of the living,’ Ps. 116:9, he would spend his days now in God's service; but lest we should think he was rash and self-confident, he adds, ‘I believed, therefore have I spoken,’ ver. 10. First, he acted his faith on God for strength, and then he promiseth what he will do. Indeed, the Christian is a very beggarly creature considered in himself. He is not ashamed to confess it. What he promiseth to expend in any holy duty, is upon the credit of his Saviour’s purse, who, he humbly believes, will bear him out in it with assisting grace.
Tenth Direction. Be sure to fortify thyself against those discouragements, by which Satan, if possible, will divert thee from thy purpose, and make thee lay aside this breastplate of righteousness and holiness, as cumbersome, yea prejudicial, to thy carnal interests. Now the better to arm thee against his assaults of this kind, I shall instance two or three great objections, whereby he scares many from this holy walking, and also lend a little help to wrest these weapons out of thine enemy’s hand, by preparing an answer to them.