The change in their hearts come from the Sacrament of Baptism.
That is not supporter by Scripture in ANY WAY.
You want to show us some scripture where someone changes their heart after they get dipped, or dipped upon???
If that was true, all you'd have to do is sneak around with a spray bottle of Catholic holy water and spray unsuspecting victims...Their eyes would be opened and their hearts turned to the Catholic religion...
Get 'em at night when they are sleeping...Just like a little baby...