We are disciples of the Buddha since countless kalpas in the past.

"...We see from the sutra that only these four bodhisattvas had been the disciples of Shakyamuni, the lord of teachings, since numberless major world system dust particle kalpas in the past; from the time he had first aroused the aspiration for and attained enlightenment, they had never followed any other Buddha, nor had they required the instruction of the theoretical and essential teachings.

Thus T’ien-t’ai says, 'The great assembly witnessed the Bodhisattvas of the Earth alone making this pledge.' He also states, “[The Buddha said of the Bodhisattvas of the Earth,] ‘These are my disciples, destined to propagate my Law.’ Miao-lo says, 'The children propagate the Law of the father.' And Tao-hsien states, “The Law embodied therein [in the Lotus Sutra] is the Law that was realized countless kalpas in the past, and therefore it was entrusted to persons who had been the Buddha’s disciples from countless kalpas in the past.' Thus these five characters of Myoho-renge-kyo were entrusted to these four bodhisattvas." - On Rebuking Slander of the Law and Eradicating Sin