I think this text and tune are sound, and I enjoyed singing it. The melody carries the text well and is memorable.
I could wish for a bit more bass movement in measures 2 and 7. Also, the harmony in measure 9 feels a bit drab; I’d suggest more traditional harmonic progression there, but it could be just me.
I agree with Rachel, and suggest that you switch the archaic pronouns to “you” instead. I think that will flow well.
I’d also suggest changing “severe mercy” because “mercy” doesn’t fit with the meter.
