Complex sentence: Bona Dea's rites not only required the use of strong sacrificial-grade wine (temetum) but simultaneously required its disguise; the wine was "lac" (milk) and its container a "mellarium" (honey jar).
Split into simpler sentences: Bona Dea's rites did not merely permit the use of sacrificial-grade wine (temetum); they simultaneously required its disguise. The wine was called "lac" (milk) and its container a "mellarium" (honey jar).