To work without attachment is to work without the expectation of reward or fear of any punishment in this world or the next. Work so done is a means to the end, and God is the end.
Work, apart from devotion or love of God, is helpless and cannot stand alone.
Through selfless work, love of God grows in the heart. Then through his grace one realizes him in course of time. God can be seen. One can talk to him as I am talking to you.
Through selfless work, love of God grows in heart.
To work without attachment is to work without the expectation of reward.