梵網經菩薩戒本疏 6.216

6.216

五、闕緣者，闕初緣結重罪非犯戒，闕次緣結重方便，闕後二緣皆方便，可知。

Fifth, missing conditions: missing the first condition incurs a heavy offense that is not a breach of precepts; missing the second condition incurs a heavy preparatory [offense]; missing the latter two conditions are both preparatory [offenses], as can be known.