法華義疏 4.140

4.140

上正明二乘眾生並皆成佛，今通明五乘眾生並皆成佛。以破昔謂行五乘之因別得五乘之果，是故今明因無異感、果無別詶，故並皆成佛。所以前明二乘成佛、後明五乘成佛者，凡有二義：一者、此教之興正為二乘，傍及人天，故前明也。二者、舉人天乘破二乘保執義，佛言我以佛眼見過去，人天一念善根尚並已成佛竟，故知無有灰身滅智同於大虛畢竟永住二乘不成佛也。

Above, it specifically clarified that sentient beings of the two vehicles all attain buddhahood; now, it comprehensively clarifies that sentient beings of the five vehicles all attain buddhahood. This refutes the past notion that practicing the causes of the five vehicles separately obtains the fruits of the five vehicles; therefore, it is now clarified that causes have no distinct inductions and fruits have no separate recompenses, so that all attain buddhahood. As for why the buddhahood of the two vehicles was clarified first and the buddhahood of the five vehicles clarified later, there are broadly two meanings: First, the arising of this teaching is principally for the two vehicles, and only collaterally reaches humans and gods; hence it was clarified first. Second, citing the vehicle of humans and gods refutes the clinging attachment of the two vehicles: the Buddha states, 'With my buddha-eye, I have seen that even those in the past with a single thought of good roots among humans and gods have already attained buddhahood.' From this we know that there is no such thing as reducing the body to ashes and extinguishing wisdom to become identical to the great void, eternally dwelling in the two vehicles and never attaining buddhahood.