The phrase "would god it came to pass" most nearly means a. "i can't know if it will happen." b. " don't let it happen." c. "i wish that it had happened." d. " goodness it didn't happen."

This phrase / excerpt from Thomas Hardy's poem is a sad poem which gives subject to aging. The phrase had reference to him wishing it had happened. The last line was implying / talking about experience in love which says, "My heart had shrunk as thin!". 

The answer is C.

Allusion and illusion. an allusion is an indirect reference, whereas an illusion is something that is unreal or incorrect. each of the nouns has a related verb form: allude “to refer indirectly to,” and illude (not a very common word), which may mean “to delude or deceive” or “to subject to an illusion.”