Throughout the Clone Wars and Beyond, Obi-Wan Kenobi served as a valiant Knight of the Jedi Order, hoping to keep the peace wherever he went. During these missions however, he wielded a blue lightsaber, one commonly associated with those Jedi who preferred combat and fighting, over more diplomatic ways to solve problems. Obi-Wan was known as someone who preferred to take that second option, and always try to find a peaceful resolution. So why didn’t he have a green saber, which fits far better with his philosophy and personality?
So as we know from the Canon, a Lightsaber crystals gains it color the moment it is harvested from it’s resting place, and attunes to the traits and personality of the force user who harvested it. Usually they’re collected on Ilum for Jedi, but Kyber crystals could found in many different places across the galaxy. Now as for the meaning of the different colors, well there are actually three main colors within the Jedi Order. Obviously there are way more colors, including Mace Windu’s purple, but the three main colors that were capable of being collected by Jedi were Green, Blue and Yellow.
Blue was harvested by the Jedi Guardians, who usually preferred to focus on their combat abilities and were never afraid to pull out their lightsaber. Green was harvested by Jedi Consular, who had a deep connection to the cosmic force and preferred to use the force to get them out of bad situations, and then finally Yellow, which was harvested by the Jedi Sentinnels who were a mix of both. These were considered the most relatable and powerful class of Jedi, and Palpatine was even scared of them… So given these different schools of thought, you’d probably think that Obi-Wan fits better in the class of Jedi Consular, who usually have green sabers… I mean, he even had the nickname “The Negotiator” during the clone wars, which is a key principle of the Consulars and his own Master Qui-Gon Jinn was one. So why doesn’t Kenobi have a green saber?
While it’s clear that Obi-Wan is very strong in the cosmic force and values diplomacy now, when he harvested his Kyber crystals, this wasn’t the case. As a young Jedi, Kenobi was brash, hot headed and honestly very arrogant. He constantly went head to head with his Master Qui-Gon over matters of the force and how to properly approach a situation.
On top of this, Obi-Wan deeply cared about his lightsaber combat abilities, and specifically with a focus on the defensive form, Known as Soresu or Type 3. Type 3 lightsaber combat was primarily designed to counter blaster fire and was the most defensive of the seven forms. It utilized tight moves and very subtle doges, as well as strong parries to keep it’s user safe. Over time, it Form III became a very popular form within the Jedi Order and even became the ultimate expression of non-agressive Jedi philosphy. So in a way, you’d have to be a Jedi Guardian to Master Form III, but once you did achieve that Mastery, you’d probably transition into a Jedi consular because of it’s non-agressive style…