Namu Byodo Daie Ichijo Myōhō Renge Kyō

[In the phrase Namu Byodo Daie Ichijo Myōhō Renge Kyō,] Ichijo translates as the one vehicle (the one mode of transportation). In this case, the Buddha teaching is compared to a vehicle. Why is it compared as such? It is because the power of the Buddha’s teaching can transport us human beings, with all our defilements (Bonno) suffering in this Saha World [the realm where one must endure], across the ocean of suffering to the further shore of enlightenment and the realm of the Buddha. So the character Jo (vehicle) is used. In appearance, the vehicle of the Buddha teaching may seem to be more than one, but there exists only one absolute truth after all, not two, not three. … [T]his world is the life of the Buddha and we humans are receiving a part of that life, so, we are, in effect, all siblings as children of the Buddha. We must realize this and that the only real choice for all people, in the end, is to become Buddhas. This world is originally the pure land of the Buddha; we must build a peaceful world as soon as possible. This is the only viable solution to save us all. This is the meaning of Ichijo (The One Vehicle). It is expressed completely as Byodo Daie Ichijo Myōhō Renge Kyō and encompasses all religious, philosophical and ethical ground.

Journey of the Path to Righteousness, p 28-29