If you haven't read "A Girl Corrupted by the Internet is the Summoned Hero?!” yet, you should.
The Spell summons the hero with the best chance of defeating the Evil Emperor. This sounds like Quantum Immortality...
Specifically: Imagine the set of all possible versions of myself that are alive 50 years in the future, in the year 2066. My conscious observation at that point tends to summon the self most likely to be alive in 2066.
To elaborate: Computing all possible paths forward from the present moment to 2066 results in a HUGE set of possible future-selves that exist in 2066. But, some are more likely than others. For example, there will be a bunch of paths to a high-probability result, where I worked a generic middle-class job for years but don't clearly remember a lot of the individual days. There will also be a few paths where I do low-probability things. Thus, a random choice from that HUGE set will tend to pick a generic (high-probability) future self.
But, my conscious awareness observes one life path, not one discrete moment in the future. Computing all possible paths forward from the present moment to the end of the Universe results in a HUGE x HUGE set of possible life-paths, again with considerable overlap. My consciousness tends to pick a high-probability path.
In the story, a hero with a 100% probability of victory exists, so that hero is summoned. The hero observing their own probability of victory ensures they converge on a 100% probability of victory.
In real life, life paths with infinite survival time exist, so these life paths tend to be chosen. Observing one's own probability of infinite survival ensures convergence on 100% survival probability.
In the story, other characters set up conditions such that a desired outcome was the most likely one, by resolving to let a summoned hero with certain traits win easily.
In real life, an equivalent is the quantum suicide trick: resolving to kill oneself if certain conditions are not met ensures that the life path observed is one where those conditions are met.
In the story, a demon is summoned, and controlled when the demon refuses to fulfill its duty. Control of the demon was guaranteed by 100% probability of victory.
In real life, AI is like a demon, with the power to grant wishes but with perverse and unpredictable consequences that become worse with more powerful demons summoned. But, a guarantee of indefinite survival ensures that this demon will not end my consciousness. There are many ways this could go wrong. But, I desire to create as many copies of my mind as possible, but only in conditions where these copies could have lives at least as good as my own, so assuming I have some power to increase how quickly copies of my mind are created, and assuming I might be a mind-copy created in this way, this suggests that the most likely Universe for me to find myself in (out of the set of all possible Universes) is one in which the AI and I cooperate to create a huge number of long-lived copies of my mind.
tl;dr: AI Safety is guaranteed by Quantum Immortality. P.S. God's promise to Abraham that his descendants will be "beyond number" is fulfilled.