"But the father said to his servants, 'Quick! Bring the best robe and put it on him. Put a ring on his finger and sandals on his feet. Bring the fattened calf and kill it. Let's have a feast and celebrate. For this son of mine was dead and is alive again; he was lost and is found.' So they began to celebrate. (Luke 15:22-24 NIV)

This is how the father of the prodigal son was like... = He gave love that is undeserving for his son. = He trusted his son. = He had sympathy toward his son. = He knew his son very well. = He was generous.