From Díaz del Castillo, Vol. 2, Chapter 91

When we arrived [at the temple], Moctezuma left the sanctuary of his evil Idols, which were at the top of the Great Temple. Two priests came with him, and later with great reverence to all of us and to Cortés, Moctezuma said: "[So] You want to come here, lord Malinche, to mount the summit of our Great Temple?" Cortés answered him [through the interpreter Doña Marina] that they were not too tired to do it.

Then our Captain asked Moctezuma through our interpreter: "Your Highness is indeed a very great prince and worthy of even greater things. We are rejoiced to see your cities, and as we are happy to be here at your temple, what I now beg as a favor is that you will show us your gods and Teules." Moctezuma replied that he, must first speak with his high priests, and when he had spoken to them he said that we might enter into a small tower and apartment, a sort of hall, where there were two altars, with very rich carvings on the top of the roof. On each altar were two figures, like giants with very tall bodies and very fat, and the first which stood on the right hand they said was the figure of Huitzilopochtli, their god of War; the second was the figure of Tezcatlipoca, [the god of rulers, sorcerers, and warriors]. [There was also] a niche for a portrait of Our Lady.

[After examining the Idols and the blood all over the walls.]

Our Captain said to Moctezuma through our interpreter, half laughing: "Señor Moctezuma, I do not understand how such a great Prince and wise man as you are has not come to the conclusion, in your mind, that these idols of yours are not gods, but evil things that are called devils, and so that you may know it and all your priests may see it clearly, do me the favor to approve of my placing a cross here on the top of this tower, and that in one part of these oratorios where your Huitzilopochtli and Tezcatlipaca stand we may divide off a space where we can set up an image of Our Lady and you will see by the fear in which these Idols hold it that they are deceiving you."

Moctezuma replied half angrily, (and the two priests who were with him showed great annoyance,) and said: "Señor Malinche, if I had known that you would have said such defamatory things I would not have shown you my gods, we consider them to be very good, for they give us health and rains and good harvests and seasons and as many victories as we desire, and we are obliged to worship them and make sacrifices, and I pray you not to say another word to their dishonor."

When our Captain heard that and noted the angry looks he did not refer again to the subject, but said in a cheerful manner: " It is time for your Excellency and for us to return," and Moctezuma replied that it was well, but that he had to pray and offer certain sacrifices on account of the great gratlatlacol, that is to say sin, which he had committed in allowing us to ascend his great Cue, and being the cause of our being permitted to see his gods and of our dishonoring them by speaking evil of them: so that before he left he must pray and worship.