Ran across this is my reading just now. It's not surprising but is worth jotting down so I can find it later.
In Irenaeus' Against Heresies IV 20:2 says "Truly, then, the Scripture declared, which says..." and then proceeded to quote the Shepherd of Hermas, Commandment 1. Like I said...not surprising. But there it is if you need a reference to something like that.