Be ye perfect, as your Father in heaven is (Mt 5:4
Perfect-ion is "also merciful" in Luke 6:36

"You" do the allegorical reasoning. And remember the end of the commandment: Love(God) one another, as I have loved "you".

Note: pure law has no mercy at all (all who died under Moses' law died "without mercy": Heb); and the oxymoronic mixture of grace + law having a bad end, the dead end of life + death = a dead end has mercy being hindered by the enmity thereof: law, so His grace can't (yet) be merciful to y'all until y'all let law be the dead testator of the NT, and so His grace may be of "force" (Heb 9).

The "you" of a ye/you scenario in 1Peter 5:10 is the after part of such before/after, just as "you" in: "ye" shall know the truth and the truth shall make "you" freeAnd the "you all" of the end (Rev 22:21) begins with "you". Selah.