Having since learned much more about the Dead Sea Scrolls, and having gone through several editions of the published material, which is most of what has been found, I think I can safely say that this phrase has not been found in the scrolls, at least not those that we have today.

With that said, later in 2021 I became convinced that this phrase is unlikely to have ever been part of the ideology of the mysterious sect or sects that owned the scrolls. Personally, I think it may be related to the Chassidim Rishonim (חסידים ראשונים) mentioned in some sources, but that's just a speculation. I wrote on that suggestion in a paper on Chassidim Rishonim (in Hebrew) and can link it if anyone's interested.

Having since learned much more about the Dead Sea Scrolls, and having gone through several editions of the published material, which is most of what has been found, I think I can safely say that this phrase has not been found in the scrolls, at least not those that we have today.

With that said, later in 5781 I became convinced that this phrase is unlikely to have ever been part of the ideology of the mysterious sect or sects that owned the scrolls. Personally, I think it may be related to the Chassidim Rishonim (חסידים ראשונים) mentioned in some sources, but that's just a speculation. I wrote on that suggestion in a paper on Chassidim Rishonim (in Hebrew) and can link it if anyone's interested.