When I Consider How My Light is Spent (On His Blindness) Guilt and Blame Quotes

The sonnet presents a back-and-forth of guilt and blame. The speaker feels guilty about his uselessness, but he also very subtly blames God for being so demanding. At least it seems so to him.

And there's the guilt again. Immediately after asking the question, the speaker admits that it is "fond," or foolish. Do you think that the speaker is reflecting on thoughts he has had in the past, or is the sonnet meant to be a blow-by-blow account of his present thinking?