Jesus is the Good Shepherd. Just like any shepherd, He will take care of our needs and keep us safe from danger. Just like sheep, we should follow our Good Shepherd. The audience Jesus was talking to here would have understood that reference pretty clearly; in this case Jesus went even further and informed then that He Himself was the shepherd being referred to. He also took the reference in a completely new direction. Speaking to a Jewish audience, Jesus referred to sheep, “which are not of this fold.”
Here Jesus made one of his earliest allusions to the fact that salvation was not just for the Jews, but for the whole world! Whether or not the Jews He was speaking to understood this or not is an open question, but the fact that He came to save the entire world is not. If the Jews had fully understood that, they would have been shocked. To them, being God’s chosen people meant by default that non-Jews, the Gentiles were NOT chosen.
Even today, we often have a tendency to think some are not called by our Lord, or even worthy of His call. This is simply not true. Jesus wants all the sheep of the world, those lost in sin and wandering aimlessly, to be part of His flock. No matter who we are, where we are or what our backgrounds are He will be our shepherd and lead us safely to eternity if we only hear His voice and respond.