The Bible explicitly states to neither add to nor subtract from Scripture.
The answer to the reality of these and other so-called “hard sayings” of Scripture is not to pretend they don’t exist, but to take the time to study, understand them, and teach them in the larger context of Scripture itself and the culture at the time. Of course this would preclude an unmotivated, unlearned, or lazy preacher and an equally lazy or immature congregation, but that may be too much to ask for.
““For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places.”
As a footnote to why Paul uses this idea of "wrestling" with supernatural beings.... Paul undoubtedly wrote this about “wrestling with principalities” because that is precisely what happened with Jacob when he wrestled with a principality (an angel) for his promised land.
And Paul knew we would understand that Jacob, by admitting what his name really meant “Cheater” to the angel, Jacob was repenting of his sin... and this is precisely when the Angel gave him a new name and allowed him passage...
... i.e. like Jacob/Israel we cannot enter into our promise for our own lives unless and until we repent.
Repentance is the key to how we win when we wrestle against Principalities.
Repentance is the key to how we enter into our own promise.
We are never to pick up the sword against flesh and blood “enemies” but to pray for them, mindful that “there but for the grace of God go I.”
Just because the psalter wanted God to rain destruction down on His enemies, doesn't mean God wanted to.