法華玄義釋籤 1.22

1.22

「甘露門」者，實相常住如天甘露，是不死之藥。今釋妙法能通實相，故名為門。初總序竟。

'Gate of sweet dew': the true mark is eternally abiding, like the heavenly sweet dew (amṛta), the medicine of immortality. Now explaining the wonderful Dharma provides access to the true mark, hence called a 'gate'. The initial general preface ends here.