Charles Hodge on Ephesians 6:2

V. 2. This consideration is enforced by a reference to the express command of God. The duty is so important as to be included in that brief summary of the moral law given by God on Mount Sinai. It was engraven by the finger of God on the tables of stone, Honour thy father and thy mother. Any flagrant breach of this command was, according to the Mosaic law, punished with death. To honour is to reverence; and, therefore, the command has reference to the inward feeling as well as to the outward conduct. This precept is said to be πρώτη, ἐν ἐπαγγελίᾳ. This may mean, it is the first commandment in the decalogue which has a specific promise attached; for the promise connected with the second commandment does not relate to the observance of that particular precept, but to keeping God’s covenant. Or it may mean that it is the first commandment of the second table of the law, and has a promise annexed; or, πρώτη may be taken here as in Mark 12, 28. 30, in the sense of chief, i. e. the first in importance. The sense would then be, ‘Honour thy father and mother; this is the prime commandment, the first in importance among those relating to our social duties; and it has the specific promise annexed. It shall be well with thee on the earth.’ This view of the passage is on the whole to be preferred. It is not likely that Paul would call this "the first commandment with promise," when it is in fact the only command in the decalogue which has any specific promise annexed to it. And to say that it is the first in order of arrangement in the second table of the law, not only adds nothing to its importance, but supposes the apostle to refer to a distinction between the two tables of the decalogue, not elsewhere recognized in Scripture.

The promise itself has a theocratical form in the Old Testament. That is, it has specific reference to prosperity and length of days in the land which God had given to his people as their inheritance. The apostle generalizes it by leaving out the concluding words, and makes it a promise not confined to one land or people, but to obedient children every where. If it be asked whether obedient children are in fact thus distinguished by long life and prosperity? The answer is, that this, like all other such promises, is a revelation of a general purpose of God, and makes known what will be the usual course of his providence. That some obedient children are unfortunate and short lived, is no more inconsistent with this promise, than that some diligent men are poor, is inconsistent with the declaration, ‘The hand of the diligent maketh rich.’ Diligence, as a general rule, does secure riches; and obedient children, as a general rule, are prosperous and happy. The general promise is fulfilled to individuals, just so far "as it shall serve for God’s glory, and their own good."