We need to be spiritually filled and grow so that we can also perform miracles as Jesus did. The disciples weren't spirit filled enough to understand the word of Jesus here;

Leave them alone; they are blind guides [leading blind followers]. If a blind man leads a blind man, both will fall into a pit.”

Had it been they understand Jesus and His,word,they wouldn't have asked again for the meaning. We also need to know the truth and it will surely set us free