法華玄論 2.124

2.124

九明此華雖生淤泥，泥不能染污，以喻一乘雖在三乘污泥，污泥不能染污。

Ninth, it clarifies that although this flower grows in mire, the mire cannot stain it, illustrating that although the one vehicle is situated within the mire of the three vehicles, the mire cannot stain it.