I don't believe the NT has any solid personal references to the death penalty as believed by Christians and seems to assume it is in force, whether by the Romans or otherwise. We could assume a cultural aversion to the death penalty by analogy with the Sanhedrin, who had moved their court specifically so as no-one could be put to death (such penalty could only be pronounced from a certain place) owing to the situation of the Jews in which there may have been good reason to break certain laws (they are conquered by Rome, they are in precarious positions etc.) but also because simply the Sanhedrin didn't seem to like carrying out this penalty very much. We read in the Talmud,
According to the Mishna on today’s daf if the Sanhedrin killed a single individual in the course of seven years, it was considered to be a destructive, or violent, beit din [court]. Rabbi Elazar ben Azarya says that this is true if the court killed someone every 70 years. Rabbi Tarfon and Rabbi Akiva claimed that had they been on the Sanhedrin (during the last 40 years of the Second Temple period the Sanhedrin no longer ruled on capital cases, so neither of them ever served as judges on the high court) no one would have ever been killed. In response Rabbi Shimon ben Gamliel said that such behavior would have led to a proliferation of murderers.
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Jesus seems to echo such sentiments when pronouncing his judgement on the case of the adulteress, with which the Pharisees seemed to agree. We do not see any death penalty applied to apostates, but disfellowshipping seems to have been practiced (i.e., they are no longer in the communion). The Letter to the Hebrews speaks of the DP according to the Tora (Heb 10:28). but does not apply it to Christians except in the case of Divine punishment, instead following it with:
For we know him that hath said, Vengeance belongeth unto me, I will recompense, saith the Lord. And again, The Lord shall judge his people. (Heb 10:30).
Thus he leaves the matter to God, not his people.
Paul also mentions that the Magistrates carry out the penalty as a servant of God (Rom 13:4), the powers that exist in the world (at this time Rome, Persia, etc.) are put there by God to keep the peace. Paul mentions that they use the DP but seems neither to approve nor disapprove of it, just seeming to accept, as with slavery, that is exists. This is part of his larger argument for Christians to be subject to the ruling powers (i.e., not to revolt, probably anticipating the Jewish Revolts of 70 AD and beyond that led to such catastrophe).
However, Pope Innocent I takes this passage and comments:
It must be remembered that power was granted by God [to the magistrates], and to avenge crime by the sword was permitted. He who carries out this vengeance is God’s minister (Rm 13:1-4). Why should we condemn a practice that all hold to be permitted by God? We uphold, therefore, what has been observed until now, in order not to alter the discipline and so that we may not appear to act contrary to God’s authority.
(Innocent 1, Epist. 6, C. 3. 8, ad Exsuperium, Episcopum Tolosanum,
20 February 405, PL 20,495)
Of the instances of the DP being used in the NT none are framed well. We can cite the murder (for it is a murder) of John the Baptist, executed knowingly wrongfully by Herod Antipas. Another would be the, again knowingly unjust, killing of Jesus himself, executed by a begrudging Pilate. When Jesus is on the cross, one man of the two crucified next to him says to his fellow, 'We deserve to be here for what we did, but this man has done nothing wrong', yet Jesus neither agrees nor disagrees with them, but when asked for forgiveness, says, 'Truly, I say to you, today you will be with me in paradise.' Forgiveness seems to be the key here after a sincere repentance.
We find the Divine meting out the penalty as in the case of Judas (in one version) and Ananias and Sapphira, but we don't see the Christians themselves carrying it out.
While the Mediaeval Church allowed the DP to be carried out and it was supported by Aquinas, Duns Scotus, Augustine and others, it was not carried out by the Church itself, but by the King/Court/Civil Magistrate and was largely influenced by Roman Law (Germanic tribes by and large did not have the death penalty). Criminals fleeing the DP could also find sanctuary in churches (any church). This presupposes that the Church, both figuratively and literally, is a place of peace where no killings are carried out, even if based on actual crimes (as with the adulteress who is not stoned but told to 'sin no more'). This seems to have been the Church's preferred approach.
While current Catholic and Anglican doctrine are against the DP (although many Anglicans throughout history were and remain in favour), historically the Church has had a weird relationship with it; somewhat realising it was often used as an agent of terror, tyranny and other such means, it was also part of the Tora and the Roman Law. In line with this odd relationship, the Church would not carry it out but had the King, the temporal power, do it instead, so the spiritual authority (the Church) was not blackened by it. This continued throughout the Middle Ages and beyond until it was abolished altogether.
Catholic Catechism,
The death penalty
2267. Recourse to the death penalty on the part of legitimate authority, following a fair trial, was long considered an appropriate response to the gravity of certain crimes and an acceptable, albeit extreme, means of safeguarding the common good.
Today, however, there is an increasing awareness that the dignity of the person is not lost even after the commission of very serious crimes. In addition, a new understanding has emerged of the significance of penal sanctions imposed by the state. Lastly, more effective systems of detention have been developed, which ensure the due protection of citizens but, at the same time, do not definitively deprive the guilty of the possibility of redemption.
Consequently, the Church teaches, in the light of the Gospel, that “the death penalty is inadmissible because it is an attack on the inviolability and dignity of the person”,[1] and she works with determination for its abolition worldwide.
Anglican Lambeth Conference,
The Lambeth Conference of Anglican and Episcopalian bishops condemned the death penalty in 1988:
This Conference: ... 3. Urges the Church to speak out against: ... (b) all governments who practise capital punishment, and encourages them to find alternative ways of sentencing offenders so that the divine dignity of every human being is respected and yet justice is pursued;....
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