I didn't know him, but for this reason I came baptizing in water: that he would be revealed to Israel."

 So the two disciples of John followed Jesus. It may well be that they were too shy to approach him directly and followed respectfully some distance behind. Then Jesus did something entirely characteristic. He turned and spoke to them. That is to say, he met them half way. He made things easier for them. He opened the door that they might come in. 