The point of this story is the contrast between the joyless elder son and the joyful father. It was spoken in response to the way the Pharisees and scribes begrudged the welcome that Jesus gave to sinners who out of destitution resorted to Jesus:
Luk 15:1 And all the tax-gatherers and the sinners were coming near
to him to hear him; Luk 15:2 and the Pharisees and the scribes
murmured, saying, This man receives sinners and eats with them. Luk
15:3 And he spoke to them this parable, saying,
Actually, he tells 3 parables on this theme:
- the return of the lost sheep
Luk 15:4 What man of you having a hundred sheep, and having lost one
of them, does not leave the ninety and nine in the wilderness and go
after that which is lost, until he find it? Luk 15:5 and having
found it, he lays it upon his own shoulders, rejoicing; Luk 15:6 and
being come to the house, calls together the friends and the
neighbours, saying to them, Rejoice with me, for I have found my lost
sheep. Luk 15:7 I say unto you, that thus there shall be joy in
heaven for one repenting sinner, more than for ninety and nine
righteous who have no need of repentance.
- the return of the lost drachma
Luk 15:8 Or, what woman having ten drachmas, if she lose one drachma,
does not light a lamp and sweep the house and seek carefully till she
find it? Luk 15:9 and having found it she calls together the friends
and neighbours, saying, Rejoice with me, for I have found the drachma
which I had lost. Luk 15:10 Thus, I say unto you, there is joy
before the angels of God for one repenting sinner.
- the return of the lost son
Luk 15:11 And he said, A certain man had two sons; Luk 15:12 and
the younger of them said to his father, Father, give to me the share
of the property that falls to me . And he divided to them what he was
possessed of. Luk 15:13 And after not many days the younger son
gathering all together went away into a country a long way off, and
there dissipated his property, living in debauchery. Luk 15:14 But
when he had spent all there arose a violent famine throughout that
country, and he began to be in want. Luk 15:15 And he went and
joined himself to one of the citizens of that country, and he sent him
into his fields to feed swine. Luk 15:16 And he longed to fill his
belly with the husks which the swine were eating; and no one gave to
him. Luk 15:17 And coming to himself, he said, How many hired
servants of my father's have abundance of bread, and I perish here
by famine. Luk 15:18 I will rise up and go to my father, and I will
say to him, Father, I have sinned against heaven and before thee; Luk
15:19 I am no longer worthy to be called thy son: make me as one of
thy hired servants. Luk 15:20 And he rose up and went to his own
father. But while he was yet a long way off, his father saw him, and
was moved with compassion, and ran, and fell upon his neck, and
covered him with kisses. Luk 15:21 And the son said to him, Father,
I have sinned against heaven and before thee; I am no longer worthy to
be called thy son. Luk 15:22 But the father said to his bondmen,
Bring out the best robe and clothe him in it , and put a ring on his
hand and sandals on his feet; Luk 15:23 and bring the fatted calf
and kill it, and let us eat and make merry: Luk 15:24 for this my
son was dead and has come to life, was lost and has been found. And
they began to make merry. Luk 15:25 And his elder son was in the
field; and as, coming up , he drew nigh to the house, he heard music
and dancing. Luk 15:26 And having called one of the servants, he
inquired what these things might be. Luk 15:27 And he said to him,
Thy brother is come, and thy father has killed the fatted calf because
he has received him safe and well. Luk 15:28 But he became angry and
would not go in. And his father went out and besought him. Luk 15:29
But he answering said to his father, Behold, so many years I serve
thee, and never have I transgressed a commandment of thine; and to me
hast thou never given a kid that I might make merry with my friends:
Luk 15:30 but when this thy son, who has devoured thy substance with
harlots, is come, thou hast killed for him the fatted calf. Luk 15:31
But he said to him, Child, thou art ever with me, and all that is
mine is thine. Luk 15:32 But it was right to make merry and rejoice,
because this thy brother was dead and has come to life again, and was
lost and has been found.
In the first two the loss is not the fault of the sheep or coin but the son has behaved reprehensibly and he returns with deep shame, earned poverty and his return is an act of desperation.
There is no suggestion in the 3rd parable that the returning son's fortunes are restored. In fact it is clear that all he gets from his father is a ring, a robe and a job:
Luk 15:31 But he said to him, Child, thou art ever with me, and
all that is mine is thine.
It is the extravagant party, the robe and the ring that sticks in the craw of the elder son in the same way that the joyful feast Jesus was throwing for the repentant IRS agents and other sinners. Jesus is driving home the point that penitents should be received with joy rather than focusing on their being undeserving.
So to answer the question, indeed the return of the son is not because of a change of heart but because of a change of circumstances... he was desperate:
Luk 15:14 But when he had spent all there arose a violent famine
throughout that country, and he began to be in want. Luk 15:15 And
he went and joined himself to one of the citizens of that country, and
he sent him into his fields to feed swine. Luk 15:16 And he longed
to fill his belly with the husks which the swine were eating; and no
one gave to him. Luk 15:17 And coming to himself, he said, How many
hired servants of my father's have abundance of bread, and I perish
here by famine. Luk 15:18 I will rise up and go to my father, and I
will say to him, Father, I have sinned against heaven and before thee;
Luk 15:19 I am no longer worthy to be called thy son: make me as one
of thy hired servants.
Ultimately his poverty should be presumed by the reader to not just be the winds of chance but rather the providence of his heavenly father driving him home as we see in God's dealings with Israel:
2Ch 7:13 If I shut up the heavens that there be no rain, or if I
command the locust to devour the land, or if I send pestilence among
my people; 2Ch 7:14 and my people, who are called by my name, humble
themselves, and pray, and seek my face, and turn from their wicked
ways; then will I hear from the heavens, and forgive their sin, and
heal their land.
Some background on the parable can be found in Esau's squandering of his birthright:
Heb 12:16 lest there be any fornicator, or profane person, as Esau,
who for one meal sold his birthright; Heb 12:17 for ye know that
also afterwards, desiring to inherit the blessing, he was rejected,
(for he found no place for repentance) although he sought it earnestly
with tears.
And Jonah's gourd:
Jon 4:5 And Jonah went out of the city, and sat on the east side of
the city, and there made him a booth, and sat under it in the shade,
till he might see what would become of the city. Jon 4:6 And Jehovah
Elohim prepared a gourd, and made it to come up over Jonah, that it
might be a shade over his head, to deliver him from his trouble. And
Jonah was exceeding glad because of the gourd. Jon 4:7 But God
prepared a worm when the morning rose the next day, and it smote the
gourd, that it withered. Jon 4:8 And it came to pass, when the sun
arose, that God prepared a sultry east wind; and the sun beat upon the
head of Jonah, so that he fainted; and he requested for himself that
he might die, and said, It is better for me to die than to live. Jon
4:9 And God said to Jonah, Doest thou well to be angry for the gourd?
And he said, I do well to be angry, unto death. Jon 4:10 And Jehovah
said, Thou hast pity on the gourd, for which thou hast not laboured,
neither madest it grow; which came up in a night, and perished in a
night: Jon 4:11 and I, should not I have pity on Nineveh, the great
city, wherein are more than a hundred and twenty thousand persons that
cannot discern between their right hand and their left hand; and also
much cattle?
