One and one only

To be sure, participation in Isis worship, for example, comprised a noteworthy exercise in voluntary religiousness. So, to reiterate the point, in that feature it was partially analogous to the sort of voluntary religiousness involved in becoming a participant in Christian circles. But the analogy breaks down precisely in the demand placed upon all Christians that they must make their Christian commitment the exclusive basis of their religious identity. In short, early Christianity was the only new religious movement of the Roman era that demanded this exclusive loyalty to one deity, thereby defining all other cults of the time as rivals.— Destroyer of the gods: Early Christian Distinctiveness in the Roman World, page 86

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Modern christians could learn from that example; far too many worship and the shrines of nationalism and materialism as well as the altar of YHWH : (
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