What did josephs dream mean?

no the dream was a sign of the future his dream was here is the song I dreamed that in the fields one day the corn gave me a sign your 11 sheaves of corn all turned and bowed to mine sheaf was quite a site to see my golden sheave and tall yours were green and second rate and really rather small I dream I saw eleven stars the sun the moon and sky bowing down before my star it made me wonder why could it be that I was born for higher things than you a post in someones government a ministre or two no more song and in The brothers come to Egypt the brothers get down and bow to him