BEAT THE TAR OUT OF YOU
This was something I heard from my grandmother a lot as a small boy, especially after I disappeared for hours on my bike or on a long hike without letting her know I was going to be gone!
Meaning: As mostly attributed, to defeat someone very badly. As I believe my grandmother meant it, beating them sufficiently to return them to the path of rightousness.
Orgin: It started as an old sea phrase, to "squeeze all the tar out of the ropes" or sails as to hold on tightly, for life. It has been attributed to Herman Melville around 1850.
“I will wallop the tar out of you” appeared around 1888.
As for 'beating the tar out of' --- consider the tar in 'tarpaulin', a canvas cloth that has been stiffened and tightened by soaking in and absorbing tar. Next consider a beating so bad that it takes the 'stiffening' out of a fellow. There you have a sufficient explanation of the phrase. What's more, sticky substances --- blod, snot, sweat, salt, and grime --- may fly from the recipient of such a beating. So the analogy, though now just a dull cliche, was in the first place a vivid, true, and brutal picture.
I did find one religious reference, though I have not been able to substaiate this. "Tar" in this sense is a diminutive of "tarnation," which is a condensation of "eternal damnation," so when you beat the tar out of someone, you are essentially beating them sufficiently to return them to the path of rightousness.