Choosing the lesser of two evils is really an exercise of wisdom in the normative priority, situational priority, and existential priority. In Matthew 23:23 Jesus criticized the teachers of the law and Pharisees as hypocrites, as they gave a tenth of the spices but they neglected the more important matters of the law call mark justice, mercy and faithfulness. So clearly there’s a different level of priority in the duties and the laws of God.

So choosing the lesser of the two evils is a very situational situation. For example Jesus said the Sabbath was made for men, not man for the sabbath so the son of man is the lord even of the sabbath in Mark 2:27-28. Situationally Jesus broke the sabbath to eat in the sight of the Jewish pharisees. And also in Acts 15:20, the Apostolic committee told the gentiles that they should abstain from food polluted by idols, from sexual immorality, from the strangled animals and from blood which is not part of the law, but a situational priority.

Now we can apply the comparison contrast for “less than two evils” for example Nazis at the door knocking at the door, “would you hand over the innocent Jews?” You either lie or protect the Jews. It’s a matter of prioritizing seeking the greater good and the higher law. In the same situation in Exodus 1, Frame wrote about the Hebrew wives lied to Pharaoh in order to save Hebrew babies. And God praised the Hebrew midwives for saving the Hebrew babies, but if you look at it, the Hebrew midwives lied which is supposedly a sin. This clearly speaks of the lesser evil of the two, either to lie or kill the babies. Same case for Rahab who lied to the army of Jericho about the two Jewish spies that hid in her artic, because she feared God of Israel. It’s a common sense to know that killing babies is a far greater evil than to lie. If we extend that to the election we get to look at the casting our vote for example, for the lesser of two evils, and coincidentally, we are faced with policy of killing babies by abortion or looking at the character of another candidate some decades ago.

This is a well framed answer, but as a response, how do you ensure this approach is not susceptible to pragmatism or avoid the charge that it selects its ethics on the basis of each person’s situation?

Clearly there are different levels of sin, some sins are worse than the others. (Frame, Doctrines of Life, 225). Westminster larger catechism 151-52 tells us that some sins are worse than others. Jesus also said in Luke 10: ¹¹ ‘Even the dust of your town we wipe from our feet as a warning to you. Yet be sure of this: The kingdom of God has come near.’ ¹² I tell you, it will be more bearable on that day for Sodom than for that town.

Luke 12:47–48 (ESV)

⁴⁷ And that servant who knew his master’s will but did not get ready or act according to his will, will receive a severe beating. ⁴⁸ But the one who did not know, and did what deserved a beating, will receive a light beating. Everyone to whom much was given, of him much will be required, and from him to whom they entrusted much, they will demand the more.

Therefore we can legitimately argue for the lesser of the two evils and its completely found in scriptures, in fact, both from the Lord Jesus himself.

So this is clearly beyond just the situational perspective. Interestingly, the just concluded presidential election has torn Christianity apart in supporting them. I would argue we should vote for the lesser of the two evils. In terms of policy, one has only good and hardly any evil, and the other is literally overflowing with evils form abortion till 12^th week, to transgenderism using tax dollars, and cheating using illegals to bolster their vote, of a level unseen or heard in any country that I know of.