Update on I John 1:7

I attended a seminar this past weekend on 1 John. Though I was disappointed by the lack of documentation given for various assertions, there was one little tidbit that was a probable answer to something I have stumbled over for many years. 1 John 1:5 says God is light.

1 John 1:5 This then is the message which we have heard of him, and declare unto you, that God is light, and in him is no darkness at all.

A mere two verses later we read:

1 John 1:7 But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin.

If God is light, why does it say He is in the light? Our God is the prime deal. He isn’t just within the light shown from somewhere else. The wording has bothered me for many years. I have not understood it. Every other English version I have checked is consistent with this wording. Our speaker this past weekend suggested that the punctuation is off. He suggested the following:

1 John 1:7 But if we walk in the light as He is, in the light we have fellowship one with another….”

I checked out the Greek to the best of my ability. It seems to work there. (Our speaker has much more knowledge of Greek than I do.) I am slow and cautious about fully embracing new concepts such as this, but this looks like a plausible explanation. Anyone else have anything to add here?