妙法蓮華經玄贊 5.314

5.314

贊曰：引己為證。「保」者當也信也證也。「任」者保也安也可也持也。與汝當可為保信證明，安可任持言可保，言終不虛也。「汝等但取勿生疑惑」，三乘之法實是好法，我為汝保，汝但取之勤加精進，如世買物無人保信知物非真，有保買之當知勝物；三乘亦爾我能保之，生死非真我不能保也。

The Commentary says: Citing himself as evidence. "Bao" (保) means to guarantee, to believe, or to attest. "Ren" (任) means to assure, to set at ease, to permit, or to uphold. [It means:] "I can serve as a trusted guarantee and proof for you; setting you at ease, I can uphold it; my words can be trusted, and my words will never be false." "You need only adopt them, and do not give rise to doubts": the Dharma of the three vehicles is truly a fine Dharma; I guarantee it for you, so you need only adopt it and diligently redouble your vigor. It is like purchasing goods in the world: if no one guarantees them, one knows the goods are not genuine; if there is a guarantor, in buying them one knows they are superior goods. The three vehicles are also like this: I can guarantee them. Saṃsāra is not genuine, so I cannot guarantee it.