Seven seasons into Brooklyn Nine-Nine, viewers can easily see how much Jake has grown up. The Jake Peralta of Season 7 is very different from the Jake Peralta of Season 1. From the very first episode, we can see progress and character development. While the loveable, fun energy has remained, Jake has now transformed himself into a responsible adult.
Terry says in the pilot that the only mystery Jake hasn't been able to solve is the mystery of how to grow up. Thanks to the other characters on the show, and Jake's own willingness to grow up, viewers are able to witness his maturing. Here are some ways how he has matured on the show.
Wanting To Make Holt Proud
Viewers see in the first couple of episodes, a Jake who is struggling to get Holt off his back. But eventually, Jake is more interested in impressing Holt and wants to make Holt proud of him. Holt drives him in a way the previous C.O didn't. And Jake's innate mechanism of making every authority figure into a father figure isn't as misplaced with Holt. There is genuine admiration and affection between both of them. And the ultimate need to make Holt proud of him makes Jake a much more responsible detective as well as a better person.
Charles Makes Him A Better Friend
In the earlier episodes, viewers will perceive this friendship to be extremely one-sided. Charles is over-enthusiastic and absolutely adores his best friend Jake. But Jake eventually becomes a good enough friend who deserves the love, admiration, and affection that Charles showers on him. In episodes like "Night Shift," viewers will see how Jake realizes his mistake and tries to better understand what it means for Charles to be a father. Jake picks up on Charles having more responsibility in life and in turn, becomes a better friend.
Amy Makes Him A Good Partner
In the first season of the show, viewers see a Jake who is flailing and failing as a boyfriend. He goes on terrible dates and is not able to make any of his relationships last. While his relationship with Sophia is a step above the rest, it is with Amy that he learns how relationships work.
In various instances, he learns how to better engage with her interests, not scoff at genuine emotional moments, to make small sacrifices, and to push each other to become the best versions of themselves. The mature and loving husband viewers see in the later seasons is the direct result of this.
Terry Teaches Him To Have A Life And To Take Breaks
Jake is obsessively invested in his work in the earlier seasons. He has no life and is scared of taking breaks lest someone gets hurt. Terry teaches him that people are bound to get hurt, and sometimes he can't help it. But Terry reinforced the fact that if Jake kept himself working the way he was, soon he'd not be able to help anyone out. This really makes an impact on Jake who is usually very unforgiving of himself. Terry talking to him as a friend and not a superior also helped Jake realize that there is more to life than work.
Rosa Always Puts Him In His Place
Rosa acts as a foil to him on many occasions. Jake has a tendency to get carried away by some people or some things. In his excitement, he sometimes forgets what he is supposed to be doing. In many such situations, Rosa calls him out on his behavior. This helps Jake to stop and notice what he's doing. It also allows him to get a perspective from someone he really trusts. In this manner, Rosa genuinely helps Jake become a better detective who doesn't get too carried away by things.
Gina Teaches Him Financial Responsibility
Gina is his oldest friend and Jake trusts her almost blindly. His incessant spending on unnecessary things is well known but it takes a turn for the worse when he realizes he won't be able to afford his own apartment. When Gina initially offers to buy it, he is astounded, and hurt by the fact that someone he grew up with it is more sorted than he is.
But he slowly realizes his mistakes and takes up Gina's offer and takes it a step ahead asking her to move in there, and deciding to move into Gina's starter apartment. He decides to start becoming more fiscally responsible only in his thirties, but it is thanks to Gina that he starts.
Wanting To Be A Better Father
Jake is understandably scarred by his dad leaving him when he was a child. He has serious father-issues which initially rushes him into deciding not to have kids at all. But due to an ultimatum that Amy gives, he changes his opinion on it. The difference between Jake and his dad is evident, Jake is willing to try and give it his best shot. This willingness and love for Amy allow him to change his reluctance to become a dad, to promise to try and become a better one.
Prison Makes Him A Better Detective
Prison takes away a lot of the rashness and rushed actions he used to make on the job. It makes him doubt his every action because he has seen the actual consequence of it. Having been in prison, he is terrified of false accusations or ever placing anyone innocent in there. While he thinks this experience makes him a bad detective, Holt points out how it makes him an incredibly good one. The presumption of innocence and increased empathy Jake has shown his growth after his prison sentence.
Responsibly Reckless
While the pilot episode and the earlier seasons saw a Jake who was extremely reckless and fun, he slowly but surely grows up. That doesn't mean he becomes any less childish, or less excited, or less fun. He is still essentially the same goofball at heart, but with a better understanding of the consequences of his actions.
He, therefore, matures into someone who is responsibly reckless, who does stupid, exciting, fun things but is level-headed and careful about what he does still. This quality of his makes him an extremely light-hearted and loveable adult.
His Willingness To Learn
Jake is not very set in his ways. He is someone who is willing to be taught, willing to be shown the way. While he does seem very adamant in the pilot, upon hearing Holt's story, he immediately starts to change his ways. While the growth is slow and each change comes with time, Jake has innate goodness and a genuine willingness to change his ways for the better, especially for the people around him. On every case, he learns some lessons. And fans will understand that it is his readiness to become better, which eventually leads to him becoming better and more mature.