風俗通義，書名，漢唐人多引作 《風俗通》。 東漢泰山太守應劭撰。原書三十卷，今僅存十篇，析為十卷。
據《風俗通》記載：「今殿作天井。 井者，東井之像也。 菱，水中之物。皆所以厭火也。」 東井即井宿，二十八宿中的一宿，圜淵方井，反植荷渠。 古人認為其可以克火，是希望能藉以壓伏祝融光顧，井中有水，籍以尅火。
敦煌藻井四百餘頂，繪製精緻，交木為井，繪以藻紋。
在佛教石窟中，蓮花圖案是聖潔光明的象，認為人的靈魂可從蓮花中獲得再生，進入西方極樂世界。
If we look at the pictures of various caves of the Dunhuang grottoes, we can find caisson ceilings in each of the caves as both decorations and blessing.
As we explained before, these ceilings design has the meaning of water and fire elements relationship which is at the destruction manner. In order to prevent fire, they all inherit this type of design in most of the caves.
Lotus flower is another common design being used. People at that time, they also believe life after death, lotus flower can lead to resurrection and then lead to heaven.
蓮花童子藻井
中間蓮花，四有化生童子
Lotus flower design in the middle with four holy children at the four corners.
另一個蓮花藻井設計
中間蓮花和四角童子
Another design with centered lotus flower and holy children at four corners too.
Spiral dragons design
