Romans 6:16

Know ye not, that to whom ye present yourselves as servants unto obedience, his servants ye are whom ye obey; whether of sin unto death, or of obedience unto righteousness? ["I take it for granted that ye know and believe" (Stuart) the principles, that no man can serve two masters (Matthew 6:24), and that no matter what profession he makes to the contrary, a man is truly the servant of that master to whom he habitually and continually yields a slavish obedience (John 8:34). These things which are true in the ordinary walks of life are equally true in spiritual matters, whether this obedience be rendered unto sin, which compensates with the wages of eternal death, or whether it be rendered unto God, so as to be rewarded with righteousness or justification (which is a prerequisite to eternal life). Thus it appears that, while we are not under law, we are under God; and hence under obligation to foster and preserve our relation to him as his servants, a relationship which is not lost by a single act of weakness, but which is lost if we continue in sin. "The apostle," says Scott, "demanded whether it might not be proved what master any one served by observing the constant tenor of any one's conduct. A person may do an occasional service for any one to whom he is not servant; but no doubt he is the servant of that man to whom he habitually yields and addicts himself, and in whose work he spends his time, and strength, and skill, and abilities, day after day, and year after year."]