For what reason does l. maria child not sympathize with john brown

After John Brown's arrest for raiding the Harper’s Ferry, on the 26th of October, 1859, Maria Child wrote him a letter. In the letter she was very clear that she supported Brown's desire free the slaves, but believed that the choices and actions he chose were unnecessary. His good intentions were noble, but Child was really saddened by his cruelty. In the end, Lydia ended up sympathizing with Brown and seeing him as an important figure to the cause.

This excerpt from the Maria's letter makes this point very clear:

"[...] I cannot sympathize with the method you chose to advance the cause of freedom. But I honor your generous intentions–I admire your courage, moral and physical. [...]"

She didn't sympathize with John Brown because of the cruelty in his actions. She made that clear in the letters she wrote for him. She sided with him for his good intentions but didn't like the course of action he chose. John Brown was known for defending African-American rights and his use of violence against racism and slavery in the decade before the Civil War. He was considered by pro-slavery Southerners as "a black-hearted villain".

On May 24, 1854, Brown led his sons in a raid on pro-slavery settlers. He dragged his targets out of their homes in the middle of the night and cut them with swords. Brown and his group killed five pro-slavery men and it was later known  as the Pottawatomie Massacre.

That is why L. Maria Child didn't sympathize with the way he acted.