The Gospel's Hurdle

What did the God-character do in the parables of the lost sheep and the lost coin? They threw a party to celebrate finding what was lost. What did the older brother do when the Prodigal Son's father threw him a party? He boycotted it. Are we with God in seeking out and celebrating the lost when they are found? Or are we complaining about God's gracious mission in the field? Because if we understand what we are called to do we must be willing to sacrifice to do it.