When Gwok Jing had matured as a man and become a Great in wulin, he eschewed using weaponry. He had two reasons for this: 1). his honorable-to-a-fault worldview caused him to see using weaponry as cowardly and unfair and 2). his best martial arts skill, the Hong Lung 18 Palms, was an unarmed combat technique, making weaponry redundant.
But why didn't the young Gwok Jing, who hadn't learned the Hong Lung 18 Palms yet, carry weaponry (other than his Yeung Hong dagger, which he almost never used in melee combat)? Gwok Jing's original martial arts teachers, the Gong Nam 7 Freaks, each carried a weapon. Each of the Freaks was an accomplished hand-to-hand fighter, but it was evident that their best martial arts were their weapons skills. Without carrying a weapon, how did Gwok Jing utilize his Freaks teachers' best skills?
In the Jin Yong canon, Gwok Jing was not the only young hero who did not regularly carry a weapon with him. Until he gained possession of the Gentleman Sword from Passionless Valley (and later, the Heavy Iron Sword from Dook Goo Kau Bai's grave), Yeung Gor did not usually carry weaponry with him either (he usually captured them from enemies he disarmed or borrowed them from armed friends). Cheung Mo Gei likewise did not carry weaponry regularly. Ling Wu Chung *did* typically carry a sword, but he was an exception.