The relationship between Peeta and Katniss in The Hunger Games can indeed be related to the "merciful" beatitude.
In The Hunger Games trilogy, Peeta Mellark and Katniss Everdeen's relationship can be seen as reflecting the "merciful" beatitude. The beatitude states, "Blessed are the merciful, for they shall obtain mercy."
Throughout the story, both Peeta and Katniss show mercy towards each other and those around them, even in the brutal and merciless world of the Hunger Games. One of the most notable examples of their mercy is seen during the 74th Hunger Games when Peeta joins the Careers, a group of deadly tributes. Despite Katniss knowing that this alliance puts both of them in danger, she shows mercy towards Peeta by saving his life on multiple occasions, ultimately forming a bond between them.
Moreover, Peeta Mellark demonstrates mercy during the Games by refusing to kill other tributes, even when his life is at stake. He demonstrates compassion and mercy towards the fallen tributes by refusing to succumb to the violence and brutality of the Games. His act of mercy creates a stark contrast with the expected behavior in the Hunger Games, where killing others is seen as necessary for survival.
Katniss, too, displays mercy by protecting and caring for Rue, a young tribute from District 11. Instead of seeing her as a threat, Katniss forms a bond with Rue and shows her kindness and mercy. When Rue is killed, Katniss demonstrates mercy towards her by singing a song and adorning her body with flowers, giving her a dignified farewell.
Overall, Peeta and Katniss portray the idea of mercy throughout The Hunger Games. They show compassion, forgiveness, and kindness, even in a cruel and ruthless environment. The merciful nature of their relationship allows them to find solace in each other and form a deep connection.