1. They should beware of an heartless despondency, and giving way to discouragement, and hearkening to the language of unbelief, or to the suggestion of Satan, whereby he will labour to persuade them of the impossibility of getting the work of sanctification throughed, or any progress made therein to purpose. Satan and a deceitful heart can soon muster up many difficulties, and allege that there are many lions, many insuperable difficulties in the way, to discourage them from venturing forward; and if Satan prevail here, he hath gained a great point. Therefore the believer should keep up his head in hope, and beware of multiplying discouragements to himself, or of concluding the matter impossible; for then shall he neither have heart nor hand for the work, but sit down and wring his hands as overcome with discouragement and despondency of spirit.
2. They should beware of wilfully rejecting their own mercies, and forbearing to make use of the grounds of hope, of strength and progress in the matter of sanctification, which Christ hath allowed them to make use of. There is such an evil among God's children, that they scar at that which Christ out of great love hath provided for them, and dare not with confidence make use of, nor apply to themselves the great and comfortable promises, to the end they might be encouraged; they will not take their allowance, as thinking themselves unworthy; and that it would be presumption in them to challenge a right to such great things; and they think it commendable humility in them, to stand a-back, and so wilfully refuse the advantages and helps, that make so much for their growth in grace.
3. They should beware of a careless neglect of the means appointed for advancing in holiness; for, though the means do not work the effect, yet it is by the means that God hath chosen to work the work of sanctification. Here that is to be seen, "that the hand of the diligent maketh rich; and the field of the slothful is soon grown over with thorns and nettles; so that poverty cometh as one that travaileth, and want as an armed man," Prov. xxiv. 30. It is a sinful tempting of God, to think to be sanctified another way than God hath in his deep wisdom condescended upon.
4. Yet they should beware of laying too much weight on the means and ordinances, as if they could effectuate the business. Though the Lord hath thought fit to work in and by the means, yet he himself must do the work. Means are but means, and not the principal cause; nor can they work, but as the principal agent is pleased to make use of them, and to work by them. When we lean to the means and to instruments, we prejudge ourselves, by disobliging of God, and provoking him to leave us, that we may wrestle with the ordinances alone, and find no advantage. Therefore the soul should guard against this.
5. Albeit the means can do nothing unless he breathe, yet we should beware not only of neglecting, as we said before, but also of a slighting way of performing them, without that earnestness and diligence that is required,—"cursed is he who doth the work of the Lord negligently," Jer. xlviii. 10. Here then is the special art of Christianity apparent, to be as diligent, earnest and serious in the use of the means, as if they could effectuate the matter we were seeking; and yet to be as much abstracted from them, in our hopes and expectation, and to be as much leaning on the Lord alone, and depending on him for the blessing, as if we were using no means at all.
6. They should beware of slighting and neglecting the motions of the Spirit; for thereby they may lose the best opportunity. They should be always on the wing, ready to embrace the least motion; and they should stand always ready, waiting for the breathings of his Spirit, and open at his call; lest afterward, they be put to call and seek, and not attain what they would be at, as we see in the spouse, Cant. v. 2, 3, 4, &c.
7. They should also guard against the quenching of the Spirit, 1 Thess. v. 12; or grieving of the Spirit, Eph. iv. 30, by their unchristian and unsuitable carriage; for this will much mar their sanctification. It is by the Spirit that the work of sanctification is carried on in the soul; and when this Spirit is disturbed, and put from his work, how can the work go on? When the motions of this indwelling Spirit are extinguished, his work is marred and retarded; and when he is grieved, he is hindered in his work. Therefore souls must guard against unbelief, despondency, unsuitable and unchristian carriage.
8. Especially they should beware of wasting sins, Psal. li. 10. Sins against light and conscience, such as David called presumptuous sins, Psal. xix. 13. They should beware also of savouring any unknown corruption, or any thing of that kind, that may hinder the work of sanctification.
Secondly, It were useful, and of great advantage for such as would grow in grace, and advance in the way of holiness, to be living in the constant conviction,
1. Of the necessity of holiness, "without which no man shall see God," Heb. xii. 14. "Nothing entering into the New Jerusalem that defileth," Rev. xxi. 7.