When we talk about religion in 1st Kings, we have to talk specifically about ritual. Much of the religious activity here is directly connected to the customs, traditions, rites, and ceremonies of worship—whether of God or of some other deity. Nowhere is this more obvious than in the chapters focused on Solomon's Temple. In order for Solomon and his people to achieve the ultimate communion with the Lord, they have to build a place where special rituals can be performed. It's a classic "if you build it, he will come" situation.
And of course, anytime God has a bone to pick with Israel and its kings, he usually focuses not on their mental, emotional, or spiritual infidelities, but on their symbolic infidelity through ritualistic devotion to other gods—although the two are, admittedly, probably not too easy to separate (see 11:7-9). In 1st Kings, sacramental actions speak louder than pious words.
Questions About Religion
What is the most powerful force in 1st Kings: religion, money, or physical might?
1st Kings gives a lot of attention to religious places and structures. How many can you name?
How many instances can you find in which religion is used as a political tool in 1st Kings?
Do you think the Lord is more upset when he gets supplanted by many idol gods, or by just one? Or is it all the same to him?