Putting aside the problem of "want" here (it implies change), the answer is quite simple: The infinite/eternal can come through, can be known in, our finite temporal existence through the finite. You can think of it as footprints of something outside your dimension.
Another very rough, somewhat cliché analog: If the wind "wants" to become known to beings without the sense of touch it moves water, moves objects.
Another way of saying this is the infinite can be evidenced to a finite being through the finite. The finite is, by definition, corruptible, imperfect - else it would be God.
Christianity differs from Islam and much of Judaism in this way. The bible is a finite object written by (inspired) finite beings. If this were not so, we would be confusing Paul, for example, for God. And confusing the finite for the infinite is a definition of idolatry (bibliolatry for example).
forcing the believer to rely on human testimony, instead of direct revelation?
I don't believe that is an accurate statement. It is not absolutely necessary to take another's word for what God is, one can explore for themselves.
There are so many holes to this assumption / mode of salvation:
What if the person is mentally-impaired? What if this person is from a community in an island in the middle of the ocean? What if this person is, as I asked long ago, a parasitic twin that's incapable of any cognitive function? Why do the available modes of salvation only apply to normal, healthy beings? Your assumption certainly requires that precondition.
Prophets and the follower's faith in the prophets are pre-conditions that are absolutely necessary for your belief in your flavour of divinity - without them, you need direct revelation.
The problem of time and change is still to be addressed: If divinity didn't have time, it cannot perform acts one after the other - because anything it did, would be done simultaneously with everything else that it did - since the 'being' is outside time.