Isaiah 1:15 is organized as a neat chiasm. At the center is Yahweh’s rejection of Judah’s prayers, but at the ends are references to hands:
A. in your spreading your hands
B. I will hide my eyes
C. when you multiply prayers
B’. I will not hear
A’. hands covered with blood
The A sections spread out like two hands, hands that, in the last phrase, we discover are covered with blood.