One Joy of so much anguish — Abortion

One Joy of so much anguish 1
Sweet nature has for me
I shun it as I do Despair
Or dear iniquity-
Why Birds, a Summer morning 5
Before the Quick of Day
Should stab my ravished spirit
With Dirks of Melody
Is part of an inquiry 9
That will receive reply
When Flesh and Spirit sunder
In Death's Immediately-
(F.1450/J.1420)
[1, 2] Joy, anguish, Nature:: pregnancy.
[3, 4] shun, Deapair, iniquity:: feeling of an unwed mother.
[5] Bird:: an exceptionally smart or accomplished person, frequently ironical (OED 4b).
[6] Quick:: quick with child, said of a female in the stage of pregnancy at which the motion of the foetus is felt (OED 4). the Quick of Day:: the day a baby being delivered.
[8] Dirks of Melody:: cries of the baby.
[9] part of an inquiry:: crying as the baby's inquiry to the mother.
[10] receive reply:: to sunder was the reply to the baby.
[11] Flesh:: a baby just delivered. Flesh and Spirit sunder:: to end a life.
[12] In Death's:: in Death's hand, belonging to the death.