How to tell the nuances of meaning of two phrases?

"Fulfil my obligation" suggests some sort of formal or semi-formal contract. The "obligation"--whatever it is--is recognized to exist by at least two people.

"Honor my commitment" seems a step more rarefied and personal than "fulfil my obligation". A commitment could exist only in the mind of the person who made the pledge, but all the same be absolutely binding.

One fulfils obligations to keep the world in balance. One honors commitments to keep one's moral core from eroding.

"fulfill my obligation" and "honour one's commitment"

I fulfilled my obligation by paying my dues
(an act was done, completed a duty)


I honored my commitment to attend church more often.
(a promise was made and kept)

I think Noddy hit the distinction on the head with this comment. I was trying to think of a way to explain the two without looking at what others had already posted and couldn't word it any better than she did.