Romans 14:3
Let not him that eateth despise him that eateth not; and let not him which eateth not judge him that eateth: for God hath received him. Let not him that eateth despise him that eateth not; and let not him which eateth not judge him that eateth: for God hath received him.
The one who eats is not to despise the one who does not eat, and the one who does not eat is not to judge the one who eats. The reason for this mutual forbearance is that God has received the other person. Applied to diet reform, this requires real common sense studied broadly and deeply, instead of criticizing others whose practice is not in all things in harmony with one's own. No unvarying rule can regulate everyone's habits, and no one is to make himself a criterion for all, because not all can eat the same things.
What is palatable and wholesome to one person may be distasteful and even harmful to another, since some cannot use milk while others thrive on it, some cannot digest peas and beans while others find them wholesome, and coarser grain preparations are good food for some while others cannot use them. Each may follow conscientious conviction about diet without being pressured to conform, and such differences should not cause disturbance or division among brethren. Because people differ in experience, habits, understanding, and how difficult particular duties are for them, what is called for is self-control, forbearance, and sympathy rather than judgment. The convictions of conscientious Sabbathkeepers are to be treated with the same tenderness and respect as those of other professing Christians.