Written by George Mueller (1805-1898), a Christian evangelist and orphanage director. This is part of an address he gave to ministers and workers after his ninetieth birthday.
I was converted in November, 1825, but I only came into the full surrender of the heart four years later, in July, 1829. The love of money was gone, the love of place was gone, the love of position was gone, the love of worldly pleasures and engagements was gone. God, God alone became my portion. I found my all in Him; I wanted nothing else. And by the grace of God this has remained, and has made me a happy man, an exceedingly happy man, and it led me to care only about the things of God. I ask affectionately, my beloved brethren, have you fully surrendered the heart to God, or is there this thing or that thing with which you are taken up irrespective of God?
And whatever you do, whether in word or deed, do it all in the name of the Lord Jesus, giving thanks to God the Father through him. [Colossians 3:17]