Daniel 2:41-43

And as you saw the feet and toes, partly of potter’s clay and partly of iron, it will be a divided kingdom; but there will be in it some of the durability and strength of iron, just as you saw the iron mixed with common clay. As the [ten] toes of the feet were partly of iron and partly of clay, so some of the kingdom will be strong, and another part of it will be brittle. And as you saw the iron mixed with common clay, so they will combine with one another in the seed of men; but they will not merge [for such diverse things or ideologies cannot unite], even as iron does not mix with clay.