Why can’t I just enjoy my life now and deal with God about my sins after I die? 

The Bible says that “the wages of sin is death” (Romans 6:23a).  When we commit an act of sin, no matter how big or small, we receive death in payment for that sin.  That is why all human beings die.  The Bible explains, “Wherefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned” (Romans 5:12).  But the phrase “the wages of sin is death” carries more meaning than just physical death.  The Bible also speaks of spiritual death.