Dr. Eldon Tyrell lives in a penthouse at the top of a giant pyramid—the headquarters of the Tyrell Corporation, the company responsible for manufacturing the replicants. In style, the pyramid is less Egyptian and more like a Babylonian ziggurat than anything else. This gives us a sense of the kind of dude Tyrell is: he's not just a humble scientist, toiling away in a lab somewhere—instead, he has the position and authority of a king or even a god (source).
In relation to Roy and the other replicants, Tyrell actually is a god—he's their creator. Tyrell and Roy have an enlightening exchange on the subject:
TYRELL: I'm surprised you didn't come here sooner.
ROY: It's not an easy thing to meet your maker.
TYRELL: What can he do for you?
ROY: Can the maker repair what he makes?
The answer to Roy's question is basically no—Tyrell can't give him what he wants, "more life." So Roy kills him. Considering that Tyrell is Roy's reason for being—father figure and god—this is a pretty audacious move on Roy's part. He's attacking the powerful technological forces that control his society, becoming a rebel in the extreme.
Since the pyramid seems pretty Babylonian, you can argue that the filmmakers want Tyrell to seem like a harsh pre-Biblical deity. In Babylonian mythology, the gods created human beings essentially to serve as slave labor to provide the gods with food in the form of sacrifices—they didn't love humans or intend to reward them in heaven. And that's exactly Tyrell's relation to the replicants he's created: they're just part of his business, a device to make money for him.