This is a step above the provo push in a sense where young people in happy valley (aka provo, utah) is trying to find ways around having actual intercourse because of their strict church guidelines. This is when a girl is so horny that she lets her man stick his boner in her vagina, but no movement or thrusting takes place. The boner just resides inside the vagina thus "soaking" inside it. This apparently isn't considered as intercourse....WTF!??
Girl: "I'm so hot for you right now, but we're not married so we can't have sex."
Boy: "Oh darn it all to heck! Oh wait...how about the provo soak!? That's not sex right!?"
Girl: "My goodness gracious! You're such a genius! Provo soak me now!"