Although, unfortunately, the title of the website suffers from clericalism (as if only clergy would find use in a quality lectionary resource), the Biblia Clerus website is clearly a wonderful resource.
You can search a Biblical text and its commentary to locate specific references to Sacred Scripture made by Doctors of the Church and church teachings.
You can examine commentary on the Sunday liturgy to cross-reference liturgical texts to homilies of the Church Fathers.
And much more. Enjoy.
I have already provided top online free lectionary resources. This link definitely is worth adding to that list.
Add your suggestions and comments below…