Those 'on the rock' are people who on hearing the word welcome it with enthusiasm, but they have no root; they believe for a while and fall away in the hour of trial.
he came one night to Jesus and said, "Rabbi, we know you have come from God to teach us, for no one could perform these Signs of yours unless God were with him."
But I possess a testimony greater than that of John, for the deeds which the Father has granted me to accomplish, the very deeds on which I am engaged, are my testimony that the Father has sent me.