The victory of the kingdom is won by deed of truth and love, by the heralding of the gospel, by obedience to God and His law. The employment of political and physical weapons to advance the kingdom of Christ is suicidal, for "all they that take the sword shall perish with the sword" (Matt. 26:52)—as the history of Christendom has borne out, Christ's truth is not defended by violence; by taking up the sword, the Christian will not establish the faith but will simply perish with the sword [Greg L. Bahnsen, Theonomy in Christian Ethics, pp. 403-4]
Knowing that God's standard of righteousness (which includes temporal, social relations) is as immutable as the character of God Himself, we should conclude that crimes which warrant capital punishment in the Older Testament continue to deserve the death penalty today. (Ibid., pp. 427-8)
With increased revelation concerning God, His righteous character, and His demand for holiness, these crimes acquire (if anything) greater culpability and appear even more dreadful. The gravity of sin is magnified by the light of progressed revelation. The atrocity of capital crimes is, therefore, intensified in the New Testament age. God's standards for public and civil justice have not changed, for God is immutable (as is His law, Matt. 5:17-18). Thus the death penalty for certain crimes is not simply a suggestion from God but a formal command. (Ibid., pp. 432-3)
... we must conclude that it is the moral responsibility of all magistrates to obey and enforce the law of God as recorded in the Older Testament (including its penal prescriptions for crime). (Ibid., p. 439)
While the people of Israel were in the wilderness, they found a man gathering sticks on the Sabbath day. And those who found him gathering sticks brought him to Moses and Aaron and to all the congregation. They put him in custody, because it had not been made clear what should be done to him. And the LORD said to Moses, “The man shall be put to death; all the congregation shall stone him with stones outside the camp.” And all the congregation brought him outside the camp and stoned him to death with stones, as the LORD commanded Moses. (Num. 15:32-36)
Now an Israelite woman's son, whose father was an Egyptian, went out among the people of Israel. And the Israelite woman's son and a man of Israel fought in the camp, and the Israelite woman's son blasphemed the Name, and cursed. Then they brought him to Moses. His mother's name was Shelomith, the daughter of Dibri, of the tribe of Dan. And they put him in custody, till the will of the LORD should be clear to them. Then the LORD spoke to Moses, saying, “Bring out of the camp the one who cursed, and let all who heard him lay their hands on his head, and let all the congregation stone him. And speak to the people of Israel, saying, Whoever curses his God shall bear his sin. Whoever blasphemes the name of the LORD shall surely be put to death. All the congregation shall stone him. The sojourner as well as the native, when he blasphemes the Name, shall be put to death. (Lev. 24:10-16)
It is in its practical applications that Theonomy would make people shudder. In the OT theocracy, the one who breaks the Sabbath and the one who blasphemes is to be stoned to death, regardless of whether the person is an Israelite or a sojourner. As long as the person lived in Israel, he is subject to these public civil laws. Yet here Bahnsen, if he is to be consistent with his position of maintaining not just the law in exhaustive detail but also its penal sanctions, must say that the magistrate ought to enforce these laws. And laws are laws. There is no mercy in the law. Sleep in one Sunday, and you'll be put on death roll. Use a single "OMG," and you're toast. The nature of the law is that justice is served, and thus there will be no mercy. All the repentance for sleeping in on a Sunday or mouthing one "OMG" is not going to save you from death. Needless to say, if such laws are actually implemented, more than 50% of society at the very least will be on death roll in just one week!
We have already shown the distortion of God's law by Bahnsen in his denial of the civil law, his misinterpretation of Matthew 5:17-20, and his redefinition of the ceremonial law. Here we want to just focus on the societal implications. Let's just say that having more than half the people in society on death roll has no chance at all of happening. But what is sad is how Bahnsen thinks that the Gospel of grace can coexist with this imposition of the civil law in exhaustive detail. Using the two swords doctrine in a unique manner, Bahnsen claims that the Church is still gracious because it does not actually wields the sword. Yet in Theonomy, the Church is the one that urges the State to wield the sword, on civil affairs. How is the Church gracious if she is calling for someone's death even though she is not the one doing the killing? Even in the era of Christendom, the killing of heretics was not grace to heretics, but judgment upon the church's enemies.
The Church's message of the Gospel is that our sins deserve death, but Christ's sacrifice saves us from death, for all who put their trust in Him. The Church is not to request capital punishment, or any punishment for that matter, on religious crimes, for the civil code is applicable only in the time of conquest, at Christ's second coming. Only then will the OT civil code be considered valid in a renewed civil theocracy. Now is the time of grace, the time of salvation not judgment. Civil crimes now are civil crimes, crimes against the State, not directly crimes against God's rule as in Israel in the OT.
Part of Bahnsen's apologetic for Theonomy is that it gives the modern church something to speak before those in authority as well as a biblical Christian ethic (pp. 10-11). However, sometimes not saying anything is better than saying something in error. Islamic Sharia law, which in many respects is a cut and paste of the Mosaic civil code, is impractical even in Islamic countries. So why would we think that Theonomy would function any better, especially if the Law is actually applied consistently and impersonally? Perhaps instead of having everything so cut up black and white, it might be better to actually leave things to godly wisdom, as the Bible extols.