The prodigal son’s older brother, reflecting Jonah’s anger at God for sparing the Ninevites, was upset because his scheme for earning grace through works was confounded. He watched his brother, whom he thought was unworthy of the gift of grace, receive it anyway.
The older brother became angry and refused to go in. So his father went out and pleaded with him. But he answered his father, “Look! All these years I’ve been slaving for you and never disobeyed your orders. Yet you never gave me even a young goat so I could celebrate with my friends. But when this son of yours who has squandered your property with prostitutes comes home, you kill the fattened calf for him!” (Luke 15:28-30)
Clearly, in his mind, obeying his father is not its own reward. His works merit better treatment than the prodigal son, he feels.
The fact that he views obeying his father as meriting him anything shows how far from his father his heart is. He has made obedience to his father’s commandments an idol, avoiding sin for fear he will besmirch it and separate himself from the father.
God is great. Our sin defiles us, but it does not defile Him. In all things we follow the stubbornness of our evil hearts (Jeremiah 16:12), even abusing the law into a sort of transcendental retirement plan. So God sent His Son to redeem us from our sin, shedding Jesus’ blood to consecrate us to Him, so that we may experience that ...
godliness has value for all things, holding promise for both the present life and the life to come. (1 Timothy 4:8)