Because it can't be compared to anything else, the spirit of that fills the universe in one second. At each moment that we do that, all sentient beings are saved, because we affirm the absolute value of everything. We have to do something, even if it's not possible. So the vow points to something like that. At least, that's my view of it.
Value is ascribed to something based on a comparison with something else.
My watch is better than your watch, so it's worth more. That's relative value. Absolute value has no basis like that. We can't compare with anything, so it stands on its own just as it is. At that time, there's no comparison of anything with anything else, so the absolute value of something emerges at that point.