It goes both ways

It is relatively easy to find the names of those who were godparents for your ancestor's children. Those names are big clues.

However, when the records are unindexed, finding the names of children for whom your ancestor was a godparent is not as easy. It requires manual searching of each entry. But it may be worth it, because the parents of that child could be relatives of your ancestor and provide significant clues to your research.