It's actually a really cool ability. It's extremely powerful and can turn the tide of a difficult fight in an instant if used correctly. I just have a habit of always telling myself to save powerful abilities and items until I forget about them and beat the game without ever using them. If you are interested, the spell is called "Divine Intervention" from Baldur's gate 3 and D&D 5e.

It's an ability called Divine Intervention that allows you to call upon your God to choose from: have an instant long rest (resurrecting all fallen companions in the process), get a legendary weapon, a chest full of potions and supplies, or deal a huge AOE of radiant damage. You get it at level 10, max level is 12.

It's one time use because in D&D it can only be used again after 7 days if it works, while it works perfectly every time in bg3.

It makes more sense than it sounds