In his “Dialogues with a Muslim”, Manuel II Palaiologos writes:
Now I would like to refute your pretension of attributing the highest dignity to the law of Mohammed. I will speak concisely and simply.
First there came the law of Moses, which you judge imperfect. This law set down in writing circumcision and everything that your law later took from it. Then came baptism and chrismation and our other mysteries and a better and more perfect law than the first. That our law is better than that of Moses you yourself have admitted. But then with your law there comes again circumcision and practically all the precepts of the first law.
If this is the case, how can you call it progress? Is there any right order in this? None at all, I am sure you will admit. It is like turning in circles, or going from what is higher back to what is lower.