Poeple in Sigma Chi pride themselves on the fact that the cross is their symbol, and that they base their Christian roots in Constantine and his vision. Well Constantine was a Sun Worshipper.

"So what we have here is evidence that although Constantine professed Christianity he maintained his pagan religious beliefs in the Sun-gods as well. This influence will be felt mightily at the Council of Nicea in 325 A.D. for it is here, under Constantine's influence that the Jewish Jesus, and his faith, is transformed and made to mimic the already existing Gentile Pagan religious beliefs as held by Constantine."
http://paganizingfaithofyeshua.netfirms.com/constantine_coins.htm

"Sun Worship
The real secret of Constantine and the bishops of Rome is their cunning introduction of sun worship and paganism into Christianity. It was done so shrewdly that, incredibly, it has been veiled within the faith for centuries. Through Constantine, paganism and Christianity joined hands in the Roman Empire."
http://www.marytruth.com/home/constantine-cover-up-and-sun-worship.aspx