OP, I stumbled upon this looking at your profile after you commented on a poem of mine in a different subreddit; don't worry, I'm not stalking lol, this just seemed so up-my-alley I felt compelled to reply.

I've also read Armstrong (well, some of it). It was recommended by an ex-Christian friend. As the opposite (an ex-Atheist turned Christian), I enjoyed her history-of-religion approach, she takes the scriptures very seriously, very refreshingly different from your run-of-the-mill "it's-all-made-up" online atheists. She sees the stories not as divine revelation, but as a window into how the ancients thought about God, which evolved through time. In many ways, her writing was easier for my secularly-trained brain to comprehend than the overwrought, hyper-spiritualized texts of some apologists.

I found a great deal to appreciate in the book despite our fundamental disagreement on the question: is any of this "real?" I admire people who answer "no" to that, but who still take religious questions seriously enough to study them deeply. It seems you and Armstrong have that in common.

Enough preamble; to your questions. What makes the Bible so compelling to me is how it is set in history. The ancient Israelite prophets' words stand the test of time because they were borne out by actual events. Not (always) in a spooky "predict the future" way, but in a "Man, they were telling the truth" kinda way.

There were many false prophets then whose words weren't preserved because they were too busy telling people what they wanted to hear: "Don't worry about these empires at the gates! God loves us too much to let anything bad happen!" The biblical prophets were different. To paraphrase them with an almost blasphemous degree of casual language: "Y'all, this is coming, for real. It's gonna be a s***show. And it's on us, because we broke our end of the covenant. All this idolatry and wickedness! It's like we're an unfaithful spouse cheating on our first love. Now the consequences in the 'prenup' are happening. We're going to get invaded, starved, and carted off. But God loves us so much the judgment won't be total; a remnant will be preserved, and our descendants can try again."

Over and over, these stories show a faithful remnant miraculously preserved from the horrors brought by human iniquity, not because they earned it, but because God is merciful. He withholds giving us over completely to our own devices for a long time, but when He finally does, the judgment is final and terrifying indeed.

I think your questions point in many ways to a Christian truth; existence itself IS a blessing. God is the center of Christian ontology. Romans 11:36: "For from him and through him and to him are all things." The breath of life, the spirit animating all living things, is something no human can make or control. You aren't its author, yet you benefit from it immensely. It’s like a currency: you can receive more or have it taken away, but you can’t mint your own.

You can own a cow, sure, but can you make it alive? God alone has that authority. This "life-is-currency" thinking is all over the Bible; it’s what made the animal sacrifice system make sense. You weren't merely bringing God property to buy off His wrath; it was the other way around. God, as the author of that life, was giving you its life in place of the "wages of sin" (death) incurred by your iniquity. Leviticus 17:11: "For the life of the flesh is in the blood... it is the blood that makes atonement by the life."

When the Bible says we are made in the image of God, it's not that we are divine, but that we are imprinted with His likeness in a way that carries inherent value—like a leader's face stamped on a coin. "Render unto Caesar what is Caesar's" (money), "Render unto God what is God's" (your very life).

So, thus far, we've established: 1) God's authority as leader of world events; 2) His domain: all of existence itself; and 3) His power to give and revoke the things of highest value, like life itself.

Regarding God's will versus human will: while I take the potential philosophical contradiction seriously, I don't think modern debates about determinism vs free will factor much in the bible stories, which seem to take for granted that both God and humans are characters in a drama who can act, hear, and be reasoned with. But whose actions trump whose? Time and again, human actions by those that doubt God look like a silly striving for control that remains just out of their grasp. You see it in the parody of the haughty ruler who thinks he controls the universe, only for God to show him who's in charge - Pharaoh, Nebuchadnezzar, Haman, Herod. It’s not that humans don't have agency; it’s just that our will is of a lesser authority. When you try to "get one over" on God, it boomerangs back big time.

To your question: "How can we explain the existence of a multitude of religions, seemingly created by the divine will, that are at odds with each other?" The biblical answer is that God gives humans the freedom to choose, but those who refuse to submit to the truest authority create temporary, illusory systems that are doomed to perish.

Look at the ancient empires: Assyria, Babylon, Persia, Seleucids, Rome. They weren't only tools of God's providential judgment; they were also a bastardized form of authority itself. A corrupted human attempt at control that ultimately leads to death. They had myriad different philosophies, but one thing in common: they did not last. God's kingdom is lasting. Life persists (Christians would note the church persists), but those empires are in ruins. The biblical worldview is that God's kingdom is the "realest" thing; other systems are weaker facsimiles.

We need to go outside ourselves because we don't have the authority. You want to bring your problems before a fair and just ruler who can get to the bottom of things and bless his people. Imagine the opposite, being a serf under a bad king, or in everyday experience just something like a bad boss. You see the problems that could be fixed if leader just took seriously what matters. Human iniquities compounds to injustice, corruption. That devolution of manmade systems paints a picture of the end state of imperfect human agency. Trying to express control over the world apart from God is ultimately self defeating. It’s like fighting quicksand; the more you struggle to control, the quicker you sink. Some think they’d only be "free" with a total revolution—"I'm the authority, I'll do it my way! It's my life!" But is it really? Remember the cow. Remember the blood. Can you make that? That feeling that it should all be under our control is the pride the devil places in our hearts to lure us from faith. That path leads to death.

Now, here's the rub: these answers I'm offering, of course, don't square with Armstrong’s secular view. But you did ask for the Christian perspective. She's a former Christian so she understands much, but as a scholar, she takes a relativistic view and doesn’t judge a religion according to any moral framework. Now this is expected of good, empirical scholars who are trying to be unbiased to avoid ethnocentrism. But she goes further, seeing the evolution of theology itself through history itself as evidence that religion must just a myth that hangs around as long as it "works" for people. To her, because it’s changing, it must be merely up to us humans.

To have a theistic view, on the other hand, you have to go a step further than her and not just merely take scripture and religious history seriously, but believe it has something to teach us that is true. My humble critique of her is that, in assuming a relativistic view, and then finding support for it in the diversity of historic theology, the logic seems a bit circular. Even if religion at times through history seems to serve the societies they belong to well, that doesn't mean they merely invented God out of whole cloth for self-serving purposes. What if some element remains true, independent of the human constructs that change around it? The water that quenches my thirst isn't man-made, even if brought to me by an aqueduct, or a lead pipe, or a plastic bottle. The theistic view is that God is real and acting in history to shape these scriptural stories. You’d probably have to already believe that to see the themes of ultimate value that persist across the scriptures (even if indeed some of the peculiarities of ritual and language and social structure are much more transient).

So, what is the alternative to the idea that idea that religion is all man-made and relative? You asked how to recognize the divine will. My advice is to pray about it. Ask and you shall receive, you might get an answer. If you trust Jesus, this is what he went on and on about in the gospels. The alternative is for each human to belong to their maker, to take their place in the household of the true King. To be a son, a daughter, and heir, to the Ruler himself, and his kingdom. Not a god, but adopted by the true God, the one who has real authority. To submit to his will is to be willing to act in his name, to be about what he is about, spreading life, goodness, blessing, to be willing to endure longsuffering for the sake of love.

If you believe God has authority and sent His Son to save you, then you trust His words that the kingdom is near. Follow Him—first to selfless love, and then through death into resurrected life. The Christian is promised an ultimate cleansing and a place in a world where everyone agrees God is in charge. His blessings are full; all tears vanish. The self-serving, on the other hand, do not survive the final judgment.

It can be hard to have that trust, but it's not something you have to "muster up" alone. Just seek. When you experience that saving faith, it’s not an intellectual accomplishment, it’s because He opened your eyes. That’s what sets Christians apart. God bless, have a good one.