-15,25 Cain attacked his brother Abel and killed him! The Lord spoke to Cain," Why are you so resentful and downcast if you do well you can hold your head up but if not know this that sin is crouching at the door like a wild animal looking to master you you must master it"!Psalm 50 Offer to God a sacrifice of praise . The Gospel According to Saint Mark 8 : 1113 Jesus sighed ftom the depth of His spirit and said: ", Why does this generation seek a sign "?