Exodus 2:2-23, Genesis 5-6, Exodus 15, Genesis 47:5, the entrance of the Israelites into Egypt.  This is a picture of a person's start in life, open doors to them of prospects ahead. These people never thought of any disappointment, or becoming slaves to that which promised so well and seemed so good.       

Exodus 2:23 shows a different picture - groaning because of the cruel bondage they were in, and every avenue closed to them. They were slaves to that which offered so much to them and which they never expected to be in bondage to. Every aim and desire failed and left them in a hopeless state of despair. God heard their groaning and sent Moses and Aaron with the Gospel to them. They ate the lamb because they were weak. Our past failures are met with the precious blood of the Lamb. Our weaknesses are met with the Lamb. The hardness and roughness of the way are met by the shoes on the feet, God equips us and fits us with all that is needed to start. God dealt with them so kindly and so truly that a confidence was begotten in their hearts that God would help them.     

Exodus 15, then sang they a song of praise. Jehovah triumphed over their sins and weaknesses and then over their enemies. Song comes out of sorrow. The joy that is worth while having is that joy that comes out of sorrow. Knowing the sorrow of a troubled soul groaning in bondage, these people could sing a song, Jehovah had triumphed. This is the song of Moses that all are going to sing on that great day (Revelations 15:3.). Egypt had been triumphing and Israel groaning, but now the tables were turned. Miriam sang the same song as Moses because she had the same experience. Singing was accompanied with dancing, dancing was the feet keeping time with the music^., hearts in tune with the will of God and feet moving to do it.