Amalek

 https://en.wikipedia.org/wiki/Amalek

The commandment to kill Amalekites is not practised by contemporary Jews, based on the argument that Sennacherib deported and mixed the nations, so it is no longer possible to determine who is an Amalekite. For example, Rabbi Hayim Palaggi stated:

We can rely on the maxim that in ancient times, Sennacherib confused the lineage of many nations.[43]

In addition, many rabbinic authorities ruled that the commandment only applies to a Jewish king or an organized community, and cannot be performed by an individual.[44] According to Haggahot Maimuniyyot, the commandment applies only in the future messianic era and not in present times; this limitation is almost a consensus among medieval authorities.[45]

Maimonides explains that the commandment to destroy the nation of Amalek requires the Jewish people to peacefully request that they accept upon themselves the Seven Laws of Noah and pay a tax to the Jewish kingdom. Only if they refuse must they be physically killed.[46]

In addition, the Amalekites, as a physical nation, have been extinct since the time of Hezekiah's reign, according to the Hebrew Bible.[47]

A few authorities have ruled that the command never included killing Amalekites. R' Samson Raphael Hirsch said that the command was to destroy "the remembrance of Amalek" rather than actual Amalekites;[48] the Sfat Emet said that the command was to fully hate Amalek rather than performing any action;[49] and the Chofetz Chaim said that God would perform the elimination of Amalek, and Jews are commanded only to remember what Amalek did to them.[50]