Duties of Masters to Servants
Masters also have a work to do as they stand related to their servants. And,
First, If possibly they can, to get them that fear God: ‘He that worketh deceit,’ saith David, ‘shall not dwell within my house; he that telleth lies, shall not tarry in my sight’ (Psa 101:7).
Second, But if none at the present but unbelievers can be got to do thy labour, then,
1. Know that it is thy duty so to behave thyself to thy servant, that thy service may not only be for thy good, but for the good of thy servant, and that both in body and soul. Wherefore deal with him, as to admonition, as with thy children; given him the same bread of God thou givest to them; and who knows, but that if thou with spiritual delicates bringest up thy servant, but he may become thy spiritual son in the end (Prov 29:21).
2. Take heed thou do not turn thy servants into slaves, by overcharging them in thy work, through thy greediness. To make men serve with rigour, is more like to Israel’s enemies than Christian masters (Exo 1:14). 
3. Take heed thou carry not thyself to thy servant as he of whom it is said, ‘He is such a man of Belial, that his servants could not speak to him.’ (1 Sam 25:14-17).
And the apostle bids you forbear to threaten them, because you also have a Master in heaven (Eph 6:9). As who should say, Your servants cannot be guilty of so many miscarriages against you, as you are guilty of against Christ. Wherefore do with, and to your servants, as you would have your master do with you.
4. Take heed that thou neither circumvent him at his coming in to thy service, nor at his going out. Servants, at their going into service, may be beguiled two ways.
(1.) By their masters lying unto them, saying, their work is so small and so easy, when it is indeed, if not too burdensome, yet far beyond what at first was said of it. This is beguiling of them.
(2.) The other way is, when masters greedily seek to wire-draw their servants to such wages as indeed is too little and inconsiderable for such work and labour. Both these the apostle opposeth, where he saith, ‘Masters give unto your servants that which is just,’ just labour, and just wages, ‘knowing that ye also have a master in heaven’ (Col 4:1).
As servants may be circumvented at their coming into their labour, so also they may be at their going out: which is done by masters that either change their wages, like heathenish Laban, (Gen 31:7). or by keeping it back, like those against whom God will be a swift witness (Mal 3:5).
5. Take heed that thou make not a gain of thy place, because thou art gracious, or livest conveniently for the means of grace. 
Servants that are truly godly they care not how cheap they serve their masters, provided they may get into godly families, or where they may be convenient for the word. But now, if a master or mistress should take this opportunity to make a prey of their servants, this is abominable, this is making a gain of godliness, and merchandise of the things of God, and of the soul of thy brother (1 Tim 6:5).
I have heard some poor servants say, That in some carnal families they have had more liberty to God’s things, and more fairness of dealing, than among professors. But this stinketh. And as Jacob said concerning the cruelty of his two sons, so may I say of such masters, they make religion stink before the inhabitants of the land (Gen 34:30).
In a word, learn of the Lord Jesus to carry yourselves well to your servants, that your servants also may learn something of the kindness of Christ by your deportment to them. Servants are goers as well as comers; take heed that thou give them no occasion to scandal the gospel when they are gone, for what they observed thee unrighteously to do when they were with thee. Then masters carry it rightly toward their servants, when they labour both in word and life to convince them that the things of God are the one thing necessary. That which servants are commanded to do, touching their fear, their singleness of heart, their doing what they do as to the Lord, and not to men; the master is commanded to do the same things unto them. (Eph 6:6-9).