The Christian's work is a high calling, God sent His only son into our world to die for us and we have been given the great commission... go into all the world and preach the gospel. The gospel is God's love for man, it is His plan for our lives not just for time but throughout eternity. God's goodness requires serious and earnest endeavours. We should aim at glorifying God at all times.
Because of His great sacrifice for us, we should always endeavour to do His will, and his will is not difficult, he merely calls us to love each other as He has loved us.
Happiness comes from serving and giving God praise. He who has given himself to God may say confidently that the Lord is good and through Jesus, nothing but glory is solid and lasting and abides forever.
Therefore each of us should use whatever gift we have received to serve others, as faithful stewards of God's grace in its various forms. 1 Peter 4:10
Let us by God's grace strive to do so, and fulfil the master's plan for us, for it is he who said, "All power is given unto me both in heaven and in the earth." Therefore we can become whatever He wants us to be because He is able to empower us.