Samson was strong physically, but weak morally. He was raised up to show what devotion to God was to look like but failed to be the example of that devotion. But in all of the failings of Samson, we see the grace of God towards Samson.
The parable of the lost son is a parable that brings us back to the heart of the matter, the Father's love for us. Whether you have messed up big time or are living 'a good life' we will hear that there is one who is Good, who is God and wants to fill our lives with his love.