Religion: (theistic): "1 the belief in a superhuman controlling power, esp. in a personal God or gods entitled to obedience and worship. 2 the expression of this in worship. 3 a particular system of faith and worship." Non-Theistic: "The word religion has many definitions, all of which can embrace sacred lore and wisdom and knowledge of God or gods, souls and spirits. Religion deals with the spirit in relation to itself, the universe and other life. Essentially, religion is belief in spiritual beings. As it relates to the world, religion is a system of beliefs and practices by means of which a group of people struggles with the ultimate problems of human life."
The Court Stated,
" The sole issue raised is whether petitioner falls within the definition of a "church" or a "religious society" . . . . The taxing authority urges denial of the tax exemption asserting petitioner is not a religious society or church and that it does not use its buildings for religious worship since "religious" and "worship" require a belief in and teaching of a Supreme Being who controls the universe. The position of the tax Court, in denying tax exemption, was that belief in and teaching of the existence of a Divinity is essential to qualify under the statute. . . . To construe exemptions so strictly that unorthodox or minority forms of worship would be denied the exemption benefits granted to those conforming to the majority beliefs might well raise constitutional issues . . . . We hold on this record and under the controlling statutory language petitioner qualifies as "a religious corporation or society" . . . ."
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In short the courts have held that secular humanism is a religion for free exercise clause purposes but have never held that secular humanism is a religion for establishment clause purposes. Nice place to be.
Evolution teaches that man is the result of time plus chance, that man is the center of nature. That is explicitly religious in my view.