Ocho' means passing is determined instantaneously and 'shiryu' (four elements) is 'life,' 'disease,' 'ageing' and 'death' and he taught that by cutting away from these four elements, one could rebirth in the Pure Land.
横超とは即時に往生が決まることで、四流とは即ち「生」「病」「老」「死」であり、この四流を断ち切ることで初めて浄土に往生できるとした。