Free Question

Pronounced as one letter, And written with three, Two letters there are, And two only in me. I'm double, I'm single, I'm black, blue, and gray, I'm read from both ends, And the same either way. What am I?
(try not to use google)

Read the passage. then, identify the theme that is supported by the passage. most ships cannot survive a terrible thunderstorm. the ocean is an angry beast that will tame any who try to control it. the gods have the power to control human destiny. men are willing to die to eat the delicious cattle of the gods.