He is both God and man. They thought more of his humanity than of his deity in this circumstance. They did come to him for help, they woke him up, so what is the problem. They were afraid. God will give you the grace to die.
Fear is the result of a lack of faith.
As a servant of the lord I'm not exempt from the storms of life. Experiencing the trials is not an indication of God's discipline or disfavor. God has power even over nature and my circumstances. Fear is the result of a lack of faith. It is a failure to believe that God is good and God is in control.