1. Does the first As in "As Janus..." mean because or when? I think it's because, but the translation goes "when", so it seems wrong.
2. What does "As with Janus" mean? What is the function of "with" in there? "As we can learn from Janus"? or "As is the case with Janus"? What is the meaning of "with"?
ex)Janus, the Roman god of doorways, reminds us of the importance of seeing the past and looking toward the future. The pictures of Janus show eyes, nose, and mouth on both the front and back of his head. The reason for showing him like this is to show that a doorway is both an entrance and exit.
As Janus stands in the doorway - the present - he can look forward and backward at the same time. The month of January is named after Janus, as it indicates both the end of the old year and the beginning of a fresh new year. As with Janus, we too can learn from where we've been while keeping our eyes focused on where we are going.