Desert Fathers, but no, I don't have any specific quotes, sorry...
I found the relevant relevant quotes, if anyone is interested:
ÃƒÆ’Ã‚Â¢ÃƒÂ¢Ã¢â‚¬Å¡Ã‚Â¬Ãƒâ€šÃ‚Â¢ Once two brothers came to a certain old man. It was his custom not to eat every day but when he saw them he received them joyfully and said, "A fast has its own reward, but he who eats for the sake of love fulfils two commandments: he leaves his own will and he refreshes his brothers."
ÃƒÆ’Ã‚Â¢ÃƒÂ¢Ã¢â‚¬Å¡Ã‚Â¬Ãƒâ€šÃ‚Â¢ It was said of an old man that he dwelt in Syria on the way to the desert. This was his work: whenever a monk came from the desert, he gave him refreshment with all his heart. Now one day a hermit came and he offered him refreshment. The other did not want to accept it, saying he was fasting. Filled with sorrow, the old man said to him, "Do not despise your servant, I beg you, do not despise me, but let us pray together. Look at the tree which is here; we will follow the way of whichever of us causes it to bend when he kneels on the ground and prays." So the hermit knelt down to pray and nothing happened. Then the hospitable one knelt down and at once the tree bent towards him. Taught by this, they gave thanks to God.
ÃƒÆ’Ã‚Â¢ÃƒÂ¢Ã¢â‚¬Å¡Ã‚Â¬Ãƒâ€šÃ‚Â¢ We came from Palestine to Egypt and went to see one of the fathers. He offered us hospitality and we said, "Why do you not keep the fast when visitors come to see you? In Palestine they keep it." He replied, "Fasting is always with me but I cannot always have you here. It is useful and necessary to fast but we choose whether we will fast or not. What God commands is perfect love. I receive Christ in you and so I must do everything possible to serve you with love. When I have sent you on your way, then I can continue my rule of fasting. The sons of the bridegroom cannot fast while the bridegroom is with them; when he is taken away from them, then they will fast."