What event did Douglass indicate "made him a man"?

Although those are not the words he used, Douglass sae his employment in New Bedford... the day he began working for himself and his wife, the day that he truly became a man.

I found employment, the third day after my arrival, in stowing a sloop with a load of oil. It was new, dirty, and hard work for me; but I went at it with a glad heart and a willing hand. I was now my own master. It was a happy moment, the rapture of which can be understood only by those who have been slaves. It was the first work, the reward of which was to be entirely my own. There was no Master Hugh standing ready, the moment I earned the money, to rob me of it. I worked that day with a pleasure I had never before experienced. I was at work for myself and newly-married wife. It was to me the starting-point of a new existence.