What falls from the sky that convinces Brown his wife is attending the witches' Sabbat?

It is one
of Faith's pink cap ribbons which falls from the sky and catches on the branch of a tree.is
devastated when he sees the ribbon.

When he initially leaves his wife to
venture into the forest for what he thinks is an "evil purpose," Goodman Brown is
filled with sorrow and foreboding. He is met by a man who carries a staff which bears the
"likeness of a great black snake." Goodman isn't too thrilled about walking further
into the woods, but his companion presses for a little more time to reason with Goodman. He
tells Goodman that he could always turn back for home if he remains unconvinced of the rightness
of their mission.

Goodman flatly tells his companion that his family were
ever "honest men and good Christians since the days of the martyrs," and that he would
be the first to do what he is about to do. Somehow, he's not too happy about this
prospect.

Goodman's companion tells him not to worry and that he is well
acquainted with Goodman's father and grandfather. After all, he was instrumental in helping them
carry out some pretty horrendous acts in their day. What's more, he tells Goodman that many of
the most respectable people that Goodman knows are well acquainted with him too. One of the
first people they meet on their way is Goody Cloyse. Goodman is aghast when he finds out that
she is going to the witches' assembly, as she used to be his catechism teacher.

It is at this point that Goodman strongly protests against going any further. His
companion tells him to rest, and he gives Goodman his staff to use when he is ready to move
along again. Goodman's companion then conveniently disappears. Goodman soon hears the clatter of
horses' hoofs and the voices of the minister and Deacon Gookin. By now, Goodman has had more
than enough. But worse is yet to come; he soon hears what he thinks is his wife's voice. He
calls out in a "voice of agony and desperation," but all he hears is a scream, soon
muffled by a murmur of voices that fade into far-off laughter. It is then that he finds Faith's
pink ribbon caught on a tree branch.

This convinces him that his wife is lost
and that there is no longer any good on earth because the Devil now owns the whole world. Poor
Goodman!