פירוש על מגילה 4:7

כהן שיש בידיו מומין – and similarly on his face or his feet

A priest whose hands are deformed should not lift up his hands [to say the priestly blessing].
Rabbi Judah says: also one whose hands are colored with woad or madder should not lift up his hands, because [this makes] the congregation look at him.
This mishnah teaches that priests who have something distracting on their hands, either a deformation or a discoloring should not lift up their hands because this makes the people look at them and not think about the blessing that they are receiving. The mishnah considers it crucial that the congregation focus not on the external attributes of the priest but the contents of the blessing that they are receiving.
We should note that today people refrain from looking at the priests’ hands when they are reciting the blessing and their hands are also covered with a tallit.
Since the mishnah is straightforward I have refrained from commenting below.

לא ישא כפיו – since the Kohanim are not entitled to go up in their sandals to the Dukhan (priest’s stage from which they pronounce the Priestly Blessing). And if he has blemishes on his feet, people will look at him and through this they will come to look at his hands, and one who looks at the Kohanim when they raise their hands to recite the Priestly Blessing, their eyes will become dim, because the Divine Presence rests between their hands.

אסטיס – its color is similar to Tekhelet/azure.

פואה – red roots that we paint red and we reach a definitive conclusion in the Gemara that if he would thresh in his city, that is, he was regularly with them and everyone knows of the blemishes that he has on him , or the color that is on his hands, or that the work of most of the people of the city is in that, it is permitted, for furthermore, they don’t look at him.