more wall

As promised last Sunday more designs from the wall of the church here in Bursa. The symbol closest to be represents the three persons of the Trinity, the other is a not so clear. There is an omega symbol on its side. This could be referirng to Christ who in the New Testament is called the "Alpha and Omega". I don't know what the S would stand for in this context. Both are sorrounded by what looks to me as a design based on the crown of thorns that was forced on Christ when he was crucified.