Lots of people argue that "Be fruitful and multiply" doesn't mean "keep that uterus occupied until it falls out on its own." Wow, thanks for being so understanding. Ok, ok, positive commands can be hard to quantify.
Or, wait--do we really think that? Do we ever argue about whether the Great Commission is command or promise? Is a pastor faithful if he says upon being installed at a parish, "My congregation and I will go into all the world once we've had some time together to get to know each other"? Can he say, "My ministry has been fruitful; I'm going to focus on the disciples I have and not baptize and teach any more"?
In this Ablaze!ing day and age, you'd get tarred and feathered for saying that pastors and the parishes to which they are wed should pace themselves when it comes to the Great Commission, not make more disciples than they can handle, have some fun together before they get down to the serious business of evangelism, go easy on an overextended and underhanded congregation. We all know the cost of discipleship is high, and that includes the start-up fees. But the costs don't excuse us from it.
So why does any Christian give another guff for making disciples the old-fashioned way? Does our theology and practice of Matthew 28:19-20 tell us anything about Genesis 1:28?