The letters that spell coexist make use of various religious symbols to represent the completely different religions. Here are the letters put to use as well as exactly what religious belief they really are for

C – It is a crescent moon signifying Islam

O – This is the peace symbol or pagan/Wiccan pentacle.

E – It's the male/female symbolic representation or a scientific equation.

X – This can be the Star of David and represents Judaism.

I – It's a pagan/Wiccan symbolic representation chosen.

S – It is a Oriental yin-yang symbolic representation.

T – The cross is used to represent Christianity.