Sometimes God appeals to people’s self-interest to get them to do what is right. Many of us need it, so that, through self-interest, we can overcome our self-interest.

We are shown this in the First Reading, where we find a straight-out argument between the people and God. They claim that “The Lord’s way is not fair!” They quote the famous saying, “The parents eat sour grapes, but the children’s teeth are set on edge” (Ez 18:2). Apparently their argument is that sin belongs to their fathers or mothers, not to them. So, God is punishing unjustly.

God’s reply in this reading is as follows:

The house of Israel says, ‘The Lord’s way is not fair!’
Is it my way that is not fair, house of Israel?
Is it not your ways that are not fair?

Then he shows them that punishment comes to those who actually commit an iniquity, not to those who just happen to be born of sinful parents. It is your own actions that matter. If you sin, it is fair that I punish you. If you do virtue, it is fair that I give you life.

Jesus’ parable in the Gospel takes it one step further. There we hear about a man whose father asks him to go work in the vineyard. The man says, rudely, “I will not.” Surely he would be counted as one of the sinful people described above. Or maybe he just had a headache, or was not a morning person, or whatever. But when his father leaves the house he changes his mind and goes out to work hard on the vines.

He has a brother. This one says in effect, “Yes, of course I will go out and do your will!” Isn't this exactly what God had been telling the people in the First Reading? I am sure the father in the present parable was pleased, especially after the rude reply he had gotten from his first son. Of course, as we know, this brother changed his mind and did not bother to go at all.

This second brother’s selfish interests were served by saying “yes, yes” to his father. It made him look good. But he did not trouble himself to actually do what he had promised. Self-interest did not get him to do good, but only to seem to do good.

So finally God decided to show us motivation that cannot be reduced to self-interest.

If we want motivation, as well as encouragement, solace in love, participation in the Spirit, compassion, and mercy, St. Paul says to look at what Christ did (Second Reading). Then you will not act out of selfishness, but will serve others humbly, as Christ did. This is the ultimate motivation in Christianity.

Have in you the same attitude
that is also in Christ Jesus,
Who, though he was in the form of God,
did not regard equality with God something to be grasped.

Rather, he emptied himself,
taking the form of a slave,
coming in human likeness;
and found human in appearance,
he humbled himself,
becoming obedient to the point of death,
even death on a cross.
Because of this God greatly exalted him.*

Self-interested motives are not the only ones. Just look at Christ—when you are at prayer and at Mass—and let him form you in humility.

Let God make you good.