I have been spanked "abusively" for something I didn't do. I have also been spanked when I deserved it for what was deliberate disobedience, specifically lying and other things we do as kids that might have gotten us hurt or even killed.
I spanked my kids when they deserved. Not so ironically my daughter maybe got 3 spankings her whole life while my son seemed to revel in being disobedient just to see what would happen.
My parents wrongly spanked me in red-faced anger. That's not how a punishment should be done. Ever.
Striking a child in anger is never okay either.
Unfortunately, what we know and what we do are sometimes different. I have been guilty of all of these. As parents we make those mistakes. We learn from them.
Perhaps oddly, spanking my kids taught ME a few things about what my parents went through trying to discipline me growing up. Spanking is not abuse; but it indeed can be.
Disciplining your children IS a form of love. Religion really has nothing to do with it. I have seen people who never got disciplined growing up. THAT was REAL abuse because those people ended up as hellions with no respect for others or even themselves.