Albert Barnes Commentary Hebrews 5:12

"For when by reason of the time ye ought to be teachers, ye have need again that some one teach you the rudiments of the first principles of the oracles of God; and are become such as have need of milk, and not of solid food." — Hebrews 5:12 (ASV)

For when for the time. This refers to the time that has elapsed since you were converted. You have been Christians long enough to be expected to understand such doctrines. This verse proves that those to whom he wrote were not recent converts.

Ye ought to be teachers. You ought to be able to instruct others. He does not mean to say, evidently, that they ought all to become public teachers, or preachers of the gospel, but that they ought to be able to explain to others the truths of the Christian religion. As parents, they ought to be able to explain them to their children; as neighbours, to their neighbours; or as friends, to those who were inquiring the way to life.

Ye have need. That is, probably the majority of them had need. As a people, or a church, they had shown that they were ignorant of some of the very elements of the gospel.

Again. This shows that they had been taught on some former occasions what were the first principles of religion, but they had not followed up the teaching as they ought to have done.

The first principles. The very elements; the rudiments; the first lessons—such as children learn before they advance to higher studies. The word used here is explained in connection with Romans 4:3, regarding the term elements. The Greek word is the same.

Of the oracles of God. Of the Scriptures, or what God has spoken .

The phrase here may refer to the writings of the Old Testament, and particularly to those parts which relate to the Messiah; or it may include all that God had at that time revealed, in whatever way it was preserved. In 1 Peter 4:11, it is used with reference to the Christian religion, and to the doctrines which God had revealed in the gospel. In the passage before us, it may mean the Divine oracles or communications, in whatever way they had been made known. They had shown that they were ignorant of the very rudiments of the Divine teaching.

And are become such. There is more meant in this phrase than that they simply were such persons. The word translated "are become"—ginomai—sometimes implies a change of state, or a passing from one state to another, and is well expressed by the phrase "are become." See Matthew 5:45; Matthew 4:3; Matthew 13:32; Matthew 6:16; Matthew 10:25; Mark 1:17; Romans 7:3–4.

The idea here is that they had passed from the hopeful condition they were in when they showed an acquaintance with the great principles of the gospel. They had become such that they again needed the most simple form of instruction.

This agrees well with the general tenor of the epistle, which is to preserve them from the danger of apostasy. They were verging towards it and had come to that state where, if they were to be recovered, it would have to be by being taught the elements of religion again.

Have need of milk. Like little children. You can bear only the most simple nourishment. The meaning is that they were incapable of receiving the higher doctrines of the gospel, just as little children are incapable of digesting solid food. They were, in fact, in a state of spiritual infancy.

And not of strong meat. The Greek is "strong food." The word meat, in our common usage, now denotes only animal food. Formerly, it meant food in general. The Greek word here means nourishment.