Zuko and forgiveness
When he interrupted and spoke out against a general, it was seen as a large insult and disrespect towards the general. Ozai demanded that he partake in an Agni Kai. unbeknownst to him, it was against the fire lord himself, and not the general. When the fight began, Zuko immediately asked for forgiveness. His plea was rejected, and Ozai ruthless burned his son, leaving Zuko with a lifelong reminder of that day.
Zuko was told to find and return the avatar in order to regain his honour and return to the fire nation. Zuko, and his uncle, Iroh set out to do so, and he constantly chased down the avatar. At the end of the second season, it appeared that the prince of the fire nation had changed, as he returned Appa to Aang, and showed vulnerability towards Katara, even to the point where she almost used the spirit water with special healing properties on his scar. But instead, Zuko joined forces with Azula, fighting Aaang and Katara, and imprisoning Iroh.
In the final season, Zuko found himself. The first thing he did, was he forgave himself. When he encountered his father on the day of the eclipse, he finally excused himself for his own wrongdoings, and he later joined the team, where he found new friends. He was quickly forgiven by Toph first, after burning her feet.
followed by being forgiven by the avatar himself, after they learned the art of fire bending.
after, he was forgiven by Sokka, when Zuko helped him save his father, and girlfriend, Suki.
and, finally he was forgiven by Katara, who took the longest to forgive Zuko.
But most importantly, Zuko was forgiven by Iroh, a person who by his side through thick and through thin, and who Zuko rejected when he thought his honour was on the line. But Iroh still took him back, giving him the unconditional love that Zuko needed all his life. Iroh represents the purity of forgiveness, and he demonstrates that forgiveness, allows people to bloom, like Zuko. Iroh through forgiveness teaches Zuko and teaches us that we should not let our past burden our future.