The Tomb of Rakkis was located deep underground. It was the tomb of a famous general in the history of Sanctuary.
This was where the Black Soulstone was stored. Because the Black Soulstone imprisoned the souls of the seven demon kings, it emitted an evil aura at all times. Even angels might be contaminated and corrupted by this evil aura, causing Tyrael to be unable to place the Black Soulstone in the High Heavens to look after it. Left with no choice, he could only find the Tomb of Rakkis in Sanctuary to place the Black Soulstone.
Now, there was another thing in this tomb—the imitation Kanai's Cube.
The people of the New Church of Horadrim were puzzled by Tyrael's decision because the Tomb of Rakkis had attracted the attacks of the Angel of Death, Malthael, because it stored the Black Soulstone. They didn't expect that Tyrael would still dare to store things here.
However, their trust in Archangel Tyrael made them choose to carry out the order.
