Satan hates priests. Of course he would hate the men who are able to act “in persona Christi” and bring Christ’s physical presence constantly into the world.
Thus priests are constantly under spiritual attack.
Here is part of a prayer by St. Faustina that intercedes on their behalf, asking God to protect priests from the snares of the devil.
Lord, give us holy priests; You yourself maintain them in holiness.
O Divine and Great High Priest, may the power of Your mercy accompany them everywhere and protect them from the devil’s traps and snares, which are continually being set for the souls of priests.
May the power of Your mercy, O Lord, shatter and bring to naught all that might tarnish the sanctity of priests, for You can do all things.