It’s a bold claim. And I’ve experienced the opposite many times.
God’s truth can be mixed with falsehood.
I’ve see just little lie and a lot of lie gentled tossed with truth and called truth.
Truth is truth, regardless of what it’s mixed with. Lies aren’t strong enough to negate God’s truth. But truth doesn’t seep into and fix the falsehoods either.
Oh, we try to mix them all the time, but if we pay attention, we notice they repel each other. They separate. Like oil and vinegar.
We just keep shaking them together, just hoping we can make them stick.