# hit me

"rebuke me" or "hit me so I will listen when he corrects me" 

# it will be a kindness to me

he will be acting kindly to me" 

# it will be like oil on my head

"when he corrects me, I will know that the one who corrects me is doing a good deed to me" or 2) to make his head feel better. 

# may my head not refuse to accept it

"may I accept it gladly" 

# my prayer is always against their wicked deeds

"I always pray that Yahweh will stop wicked people from doing evil deeds"