Why did G‑d test Abraham? Why does He test us? Why does an all-knowing G‑d need to test anybody? Shouldn't He know what is in our hearts without testing us?

A test is any situation that demands more from you than you cerebrate you have. In a test, if you would utilize your rational mind you would verbally express, "This is infeasible. This is not what I bargained for. I don't have to do this because it is not within my adeptness set. It is beyond who I am."

You don't pass a test with understanding, with reason. You pass a test with rock solid faith and blind perseverance.
If you were enlightened by the earlier podcast Abraham the Ultimate Revelation. The second part of this podcast with its amazing revelations is sure going to stir your spirit to enter a new spiritual arising in you.
May you be greatly blessed.
Shalom
Lyndon Berchy.