Very late in the war - January 1865 - Lee wrote the following on that subject:
"Considering the relation of master and slave, controlled by humane laws and influenced by Christianity and an enlightened public sentiment, as the best that can exist between the white and black races while intermingled as at present in this country, I would deprecate any sudden disturbance of that relation unless it be necessary to avert a greater calamity to both. I should therefore prefer to rely upon our white population to preserve the ratio between our forces and those of the enemy, which experience has shown to be safe. But in view of the preparations of our enemies, it is our duty to provide for continued war and not for a battle or a campaign, and I fear that we cannot accomplish this without overtaxing the capacity of our white population. "
Lee's opposition to slavery was tepid at best.
At least the Honorable Lee didn't follow after your horrendous,Conduct Unbecoming an Officer,torturous act's by your Union buffoons.
Jefferson Davis writing to General Robert E. Lee
We find ourselves driven by our enemies in their steady progress towards a practice which we abhor and which we are vainly struggling to avoid. Some of the military authorities of the United States seem to suppose that better success will attend a savage war in which no queer is to be given and no sex to be spared. For the present we renounce the right of retaliation on the innocent and shall continue to treat the private enlisted soldiers of General Pope's arny as prisoners of war, but if, after notice to the govenment in Washington, these savage practices are continued we shall be reluctantly forced to the last resort of accepting war on the terms chosen by our foes, until the outraged voice of the common humanity forces a respect for the recognized rules of war.
You are therefore instructed to communicate to the Commander in Chief of the Armies of the United States the contents of this letter — to the end that he may be notified of our intention not to consider any officers hereafter captured from General Pope's army as prisoners of war