I’ve read that some have tried different illustrations for the Trinity:

 -H2O being water, ice and steam (all different forms, but all are  H2O

-sun from which we receive light, heat and radiation. Three distinct aspects, but only one sun.

Not perfect.  How do you fit the Trinity into monotheism?

During his sermon, Alex pointed out that we get to know God the Son, God the Father, and God the Holy Spirit by prayer.  

Someone said: If you try to explain the Trinity, you will lose your mind. But if you deny it, you will lose your soul. 

Perhaps it is a divine dance, as Alex said.  Through it we participate in the divine life of God.

Jeanie H.