There are, the famous opening lines of the Didache state, “two paths: one of life and one of death, and the difference between the two is great.” These were some of the lines I was asked to translate when I entered seminary, and we were slotted into an Exegesis class on the basis of such testing. Jokes abound about “there are two kinds of…”. Jesus absorbed the same way of discerning humans, and he sees two sorts of humans: the few who enter the narrow gate and the many who enter the wide gate.
Probably no text is more directly offensive to the postmodern (or modern) pluralistic sensibility. One path, so Jesus states, leads to destruction; the other path leads to life. You can monkey with these words, but their implication is clear: a choice needs to be made to follow Jesus or not.
So what is the “gate”? For a long time I’ve taught that the gate is Jesus himself, or Jesus as he is known through his teachings. To enter that gate is to answer the summons to follow Jesus (you can see why I think the Sermon on the Mount is an evangelistic sermon).
That’s the narrow gate about which Jesus teaches.
What about numbers here? Is this a calculation of how many will make it and how many won’t? Maybe. It is more likely, as Allison and others have argued, that it is Semitic over-statement in a potent exhortation.