What is the positive side of Romans 6:13 about yielding your members?
The positive side is to yield yourself unto God as one alive from the dead, and yield your members as instruments of righteousness unto God. Instead of giving the body's functions to the old Adam or sin, the believer presents them to God to be what He wants.
Les explains that Romans 6:13 first forbids yielding your members as instruments of unrighteousness unto sin, which he identifies as the old Adam, the old sin nature. The positive side is the flip side: yield yourselves unto God, as those who are alive from the dead, and your members as instruments of righteousness unto God. He notes this is not God forcing obedience by the nap of the neck; God gives free will, and the indwelling Spirit constantly urges the believer. Les also connects it to Paul's statement in 1 Corinthians 15, "I die daily," and to Paul's constant pressure and suffering for the Gospel.
Neither yield ye your members as instruments of unrighteousness unto sin: but yield yourselves unto God, as those that are alive from the dead, and your members as instruments of righteousness unto God.