Is that the way forgiveness works?

I read once of a King and Queen of Hawaii, back in the old “missionary” days in the 1840’s and 50’s, who were both converted to Christianity by one of the New England missionaries who had come there.

In Hawaii back in those days, it was the custom for a brother and sister of Royal blood to marry each other and produce royal children to fill their shoes. Both the King and Queen knew that being together was “taboo”, but when caught by one of the missionaries, the King proclaimed: “Reverend, I was just going to continue to commit the sin until I know I was close to dying, and then ask Jesus for forgiveness, so I could go to Heaven”
That’s not how it’s supposed to work, I’m sure….but every once in a while after reading a day’s worth of posts and replies on this medium, I wonder if some folks nowadays don’t understand things the same way as the old King of Hawaii.