The Prodigal Son
This parable is set up by Jesus by telling two, shorter, parables: of the lost sheep and the lost coin . In them, Jesus appeals to our behavior: we go out of our way to find lost valuables.

But it gets much trickier when the lost item is even more valuable: a person. That person may be exercising their personal freedom. 

The behavior of the younger son would have been scandalous at the time. Asking for an early inheritance would have been the equivalent of telling a father, "I wish you were dead." Wasting the family wealth would have been the greatest possible shame. And for a Jewish boy to end up herding pigs 
represented the lowest imaginable degradation. If he were to show his face near home, every neighbor would have heaped abuse upon him.
Luke 15: 11 (ESV) Jesus continued: “There was a man who had two sons. 12 The younger one said to his father, ‘Father, give me my share of the estate.’ So he divided his property between them.
13 “Not long after that, the younger son got together all he had, set off for a distant country and there squandered his wealth in wild living. 14 After he had spent everything, there was a severe famine in that whole country, and he began to be in need. 15 So he went and hired himself out to a citizen of that country, who sent him to his fields to feed pigs. 16 He longed to fill his stomach with the pods that the pigs were eating, but no one gave him anything.
17 “When he came to his senses, he said, ‘How many of my father’s hired servants have food to spare, and here I am starving to death! 18 I will set out and go back to my father and say to him: Father, I have sinned against heaven and against you. 19 I am no longer worthy to be called your son; make me like one of your hired servants.’ 20 So he got up and went to his father.
“But while he was still a long way off, his father saw him and was filled with compassion for him; he ran to his son, threw his arms around him and kissed him.
21 “The son said to him, ‘Father, I have sinned against heaven and against you. I am no longer worthy to be called your son.’
22 “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. 23 Bring the fattened calf and kill it. Let’s have a feast and celebrate. 24 For this son of mine was dead and is alive again; he was lost and is found.’
( extended )
.​.. which is the reason that his heart-broken father needs to be on the look-out, and intercept his son "while he was still a long way off." Filled with compassion, the father interrupts his son's confused proposal and showers him with love.

Like the younger son, there is an enormous amount of inertia (pride, lifestyle, habit) in our lives keeping us from experiencing the outpouring of love that God is offering to every one of us.
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