Theology is one of the scientific studies. It is not a wholistic science.
Theology is the scientific research of religions, of Theos, God. Though a science about God, it is impossible to find or prove the existence or non existence of God by only the ratio. It is impossible to make any painting or sculpture about God. Not any book, no matter how many pages, will be able to describe or explain the concept of God. That is why John the Evangelist wrote about “the Word” in the first chapter of his book.
In the video one speaks about Buddhism (among more) as a religion. Buddhism is not a religion. Buddhism does not place God outside the human being, somewhere far away (in the sky, the universe, or whatever), as religions do, but inside the human being.
I have added this page about theology to be able to compare the sec cold (though interesting) theology studies with the liberating wholism, the broadening and deepening study of man and the relation with his inner deeper or higher self, the God within: Experiencing Oneness with All Existence as the divine factor.