Hebrews 13:9

Be not carried away by divers and strange teachings: for it is good that the heart be established by grace; not by meats, wherein they that occupied themselves were not profited.

There is, to be sure, a certain complexity in divine revelation; everything is not on the surface, and no casual or perfunctory reading of it will provide full understanding of it; but despite this, the vast body of scriptural truth is frequently referred to as "truth," in the singular, by the divine writers, emphasizing its essential unity and cohesiveness (2 John 1:1:9, etc.). Contrasted with this relative simplicity of the truth, the diversity and novelty of all kinds of theories, teachings, and speculations of people clamor incessantly for the Christian's attention. The mention of "meats" suggests the various Old Testament restrictions concerning things clean or unclean were demanding and receiving attention from the Christians who received Hebrews, despite the fact that all such restrictions had been removed (1 Timothy 4:1-5).

The proclivity of the whole human race to save themselves by some kind of diet is an amazing characteristic of "homo sapiens". Long after Christ himself made "all meats clean" (Mark 7:19), even the apostle Peter protested a vision from heaven, saying, "Not so, Lord, for I have never eaten anything that is common or unclean" (Acts 10:14). There were possibly large numbers of the original readers of Hebrews who could have said the same thing. The long centuries of preoccupation by Roman Catholics with their "fish on Friday" syndrome, various vegetarian cults, and right down to the latest enthusiasm for polyunsaturates or protein diets, to say nothing of the aversion of millions of Asiatics for swine's flesh - all these things show how deeply ingrained in human nature is preoccupation with meats. How far better it would be if people could be established by grace, that is, concerned with the knowledge and love of God, instead of being caught up in the observance of some diet, especially where religious considerations are involved. Long ago, the Master taught that it is not what people eat, but what they THINK that causes most of the real troubles besetting the race of man. Should we say that it's not what men eat, but what's eating them, that hurts! What a man eats is of secondary importance, "because it goeth not into his heart, but into his belly, and goeth out into the draught" (Mark 7:19). No wonder, then, that preoccupation with meats is a thing with utterly no profit in it.