But the gift of God. God gives to those who turn from sin, life eternal. It is his gracious gift, conditioned on refusing to be the servant of sin longer, and is through Christ. (Peoples New Testament)

Rom 6:21-23
The pleasure and profit of sin do not deserve to be called fruit.  Sinners are but ploughing iniquity, sowing vanity, and reaping the same. Shame came into the world with sin, and is still the certain effect of it.  The end of sin is death. Though the way may seem pleasant and inviting, yet it will be bitterness in the latter end. From this condemnation the believer is set at liberty, when made free from sin.  If the fruit is unto holiness, if there is an active principle of true and growing grace, the end will be everlasting life; a very happy end!  Though the way is up-hill, though it is narrow, thorny, and beset, yet everlasting life at the end of it is sure.  The gift of God is eternal life. And this gift is through Jesus Christ our Lord.  Christ purchased it, prepared it, prepares us for it, preserves us to it; he is the All in all in our salvation. (Matthew Henry)

Rom 6:21 (10) What fruit had ye then in those things whereof ye are now ashamed? for the (u) end of those things [is] death.

(10) An exhortation to the study of righteousness and hatred of sin, the contrary results of both being set down before us.

(u) The reward or payment. (Geneva Bible Translation Notes)

 

Every man is the servant of the master to whose commands he yields himself; whether it be the sinful dispositions of his heart, in actions which lead to death, or the new and spiritual obedience implanted by regeneration. (Matthew Henry)

Righteousness — The case is one of emancipation from entire servitude to one Master to entire servitude to another, whose property we are (see on Romans 1:1).  There is no middle state of personal independence; for which we were never made, and to which we have no claim.  When we would not that God should reign over us, we were in righteous judgment “sold under Sin”; now being through grace “made free from Sin,” it is only to become “servants to Righteousness,” which is our true freedom. (A Commentary on the Old and New Testaments by Robert Jamieson, A. R. Fausset and David Brown)

 

The apostle rejoiced now they obeyed from the heart the gospel, into which they were delivered as into a mould.  As the same metal becomes a new vessel, when melted and recast in another mould, so the believer has become a new creature.  And there is great difference in the liberty of mind and spirit, so opposite to the state of slavery, which the true Christian has in the service of his rightful Lord, whom he is enabled to consider as his Father, and himself as his son and heir, by the adoption of grace.  The dominion of sin consists in being willingly slaves thereto, not in being harassed by it as a hated power, struggling for victory.  Those who now are the servants of God, once were the slaves of sin.  (Matthew Henry)

Whom ye obey: "...such who obey sin, are the servants of sin; they are at the beck and command of sin; they give up themselves to the service of it with delight and diligence, and are perfect drudges to it: this is a very unhappy situation; their service is very unreasonable; and they are rendered incapable of serving God, for no man can serve two masters; they are hereby brought into the drudgery of the devil; into a state of bondage, out of which nothing but grace can extricate them; into a very mean and contemptible condition..." (Dr. John Gill)

To be under the law and under sin signifies the same thing, with respect to whose who are not sanctified, and on the other hand to be under grace and righteousness is in harmony with those that are regenerated.  Now these are contraries, so that one cannot agree with the other: therefore let righteousness expel sin. (Geneva Bible Translation Notes)

 

Rom 6:14 Sin shall not have dominion over you - It has neither right nor power.  For ye are not under the law - A dispensation of terror and bondage, which only shows sin, without enabling you to conquer it.  But under grace - Under the merciful dispensation of the gospel, which brings complete victory over it to every one who is under the powerful influences of the Spirit of Christ. (John Wesley)

 The Association for Christian Conferences, Teaching & Service, (ACCTS), Christian Military Fellowship (CMF), Officers Christian Fellowship (OCF) and other Christian organizations invite you to help us “pray our military forces through the war on terror.”

One of the best books you could ever read is "The Holy War" by John Bunyan.  There is even a version that has been updated into the modern English.  Inside this wonderful text you will find the best manual on warfare ever penned.