the song seems to imply that Jesus is ignoring the dad's pleas because they didn't do what was right, by loving their son seemingly only on what he did rather than undonditionally, they failed to truly learn the depth of his sacrifice,
which is unconditional love, and it's not easy,
but by asking god why their son has not made them happy, Jesus smiles as if to say, remember who gave his only son for you, be happy you have a son at all.
I believe the song is about being happy with what you have.
the song seems to imply that Jesus is ignoring the dad's pleas because they didn't do what was right, by loving their son seemingly only on what he did rather than undonditionally, they failed to truly learn the depth of his sacrifice,
which is unconditional love, and it's not easy,
but by asking god why their son has not made them happy, Jesus smiles as if to say, remember who gave his only son for you, be happy you have a son at all.
I believe the song is about being happy with what you have.