What applies to love applies equally to hate -- and maybe also to fear

The mishnah at Avot 5:19 begins with the words:

Any love that depends on a specific thing, if that thing is lost, to too is that love; and if it doesn’t depend on anything, it is never lost.

In “Hate: Curable and Incurable”, Covenant and Conversation: Deuteronomy, Renewal of the Sinai Covenant, 2019) Rabbi Lord Jonathan Sacks opens the possibilities contained in these few words by arguing persuasively that this proposition does not apply to love alone. It also applies to hate. In doing so, it explains an apparent anomaly in the Torah’s commands. This anomaly relates to how the Children of Israel should view the Egyptians, who had enslaved, oppressed and exploited them for centuries, even attempting genocide, and the Amalekites, who attacked them just once in the desert. 

The Torah commands that we are not to hate the Egyptians (Deuteronomy 23:8). We are however obliged to maintain perpetual hostility against the Amalekites (Exodus 17:16), even though we suffered far more at the hands of the Egyptians. Why should this be? 

An explanation is offered that, while both the Egyptians and the Amalekites hated the Children of Israel, the Egyptians had some reason for doing so: they saw this strong and increasingly populous alien tribe within their borders as a threat to their security (Exodus 1:19-20).  This reason might have been irrational and unfounded, but it was genuinely held. Once this alien tribe had departed, the reason for the Egyptians’ hatred departed too and, with it, the hatred itself. The hatred of Amalek however had no cause. A hatred that has no cause is a hatred that has no end.

It is worth considering whether this argument can be applied not only to hatred but to another word that is regularly contrasted with love: fear. Prima facie, the answer is yes, or at least it should be. If there is a reason why a person is afraid of anything—be it a dog, the dark, an unwelcome event, or another person—it is possible to address the cause of that fear. But where a fear is not conditioned upon anything it all and is quite irrational, it may never be possible to eradicate it.