I’ve always read this line as something so smelly that the odor could reach up to heaven, that the reach of the stink is so long, the distance so great.
But I just realized it could also be a personification of heaven. That is, maybe this deed doesn’t stink to anyone on earth but in heaven, it smells abominably- like the way certain smells smell good to some people and awful to others. There are a lot of perfumes like that – wherein the wearer thinks it smells great and some people AROUND them would disagree.
The Hamlet Project 