Criticism of Phyllis Wheatly's poem "On Being Brought"

Phyllis Wheatly’s poem “on Being Brought” seems to be her attempt to understand or justify her being a slave. The poem reads as thus: 'TWAS mercy brought me from my Pagan land, Taught my benighted soul to understand
That there's a God, that there's a Savior too: Once I redemption neither fought now knew,
Some view our sable race with a scornful eye,
"Their colour is a diabolic die."
Remember, Christians, Negroes, black as Cain,
May be refin'd, and join th' angelic train. By using verses that referred to her homeland of Africa in a negative way such as “Twas mercy brought me from my Pagan Land” is her saying that God allowed her to be brought to America and sold into slavery in order to become a Christian. Could it be justifiable to say that a God of love, mercy and grace would allow...