What surprises Parvana about the Talib soldier with the letter?

Parvana is surprised to find that the Talib soldier who brings her a letter is actually compassionate and kind, showing a side of humanity that contrasts with the harshness of the Taliban regime. He treats her with respect and even offers a small gesture of understanding, which challenges her preconceived notions about all soldiers being cruel. This moment reveals the complexity of individuals within oppressive systems and highlights Parvana's struggle to maintain hope amidst adversity.