As Grenouille leaves the laboratory, he feels afraid to be giving off an odor for the first time. He decides to test his perfume in an anonymous environment, so he decides to walk through the town.
Grenouille doesn't identify with his humanity or feel human, hence his fear to smell like one.
Grenouille is used to being ignored in public, as many people simply aren't aware he exists thanks to his lack of smell. However, here in Montpellier, Grenouille sees that he's being noticed in the first time, and not in a bad way. Grenouille passes a wedding leaving the cathedral and joins the crowd waiting to see the bride. The crowd doesn't notice he's any different, and Grenouille feels immense joy. He feels a child at his knee and lifts her up so she can see. Both the child and the child's mother are thrilled.
Grenouille's façade of "passing" as normal and human is complete, and further, the acquisition of a smell can be seen as one way in which Grenouille is beginning to attain true adulthood and coming of age. The child's reaction here shows just how effective Grenouille's perfume is, as it even makes him seem kind and trustworthy.
When the bride and the wedding party finally walk through the crowd, Grenouille's joy turns to a "wicked feeling of triumph." He finds he's no longer afraid of people and hardly hates them, but his contempt for humans remains strong, because they smell and are so easily fooled.
It's important to note that Grenouille's success at passing means that he sheds some of his fear of people. He understands now that he can control them and they no longer hold power over him.
When the crowd disperses, Grenouille enters the church and sits down. He feels content at his awareness of his genius and his newfound power. Grenouille knows now that he will be able to create a superhuman, angel's scent, which will make anyone who smells it immediately love Grenouille. It will be like his inner fantasies in real life, and his power will be inescapable, as inhalation is necessary to live.
Grenouille sits plotting and decides that he wants to create this perfume purely because he's evil. Inhaling the incense in the church, Grenouille thinks that God stinks and is either being swindled, as his incense in the church isn't pure, or is a swindler just like Grenouille is.
As Grenouille grows and comes of age, his self-knowledge grows too. Here he explicitly sets himself as equal or superior even to God, based on God’s perceived acceptance of impure incense.