Hebrew repetitions for emphasis

From the 1808 edition of President Edwards' works:

As to that objection which some have made, that the phrase, dying thou shalt die, is several times used in the Books of Moses, to signify temporal death, it can be of no force: For it has been shewn already, that the same phrase is sometimes used in Scripture to signify eternal death, in instances much more parallel with this. 

But indeed nothing can be certainly argued concerning the nature of the thing intended, from its being expressed in such a manner. For it is evident that such repetitions of a word in the Hebrew language, are no more than an emphasis upon a word in the more modern languages, to signify the great degree of a thing, the importance of it, or the certainty of it, etc. 

When we would signify and impress these, we commonly put an emphasis on our words: instead of this, the Hebrews, when they would express a thing strongly, repeated or doubled the word, the more to impress the mind of the hearer; as may be plain to everyone in the least conversant with the Hebrew Bible. 

The repetition in the threatening to Adam, therefore only implies the solemnity, and importance of the threatening. But God may denounce either eternal or temporal death with peremptoriness and solemnity, and nothing can certainly be inferred concerning the nature of the thing threatened, because it is threatened with emphasis, more than this, that the threatening is much to be regarded. 

Though it be true, that it might in an especial manner be expected that a threatening of eternal death, would be denounced with great emphasis, such a threatening being infinitely important, and to be regarded above all others.

Kindle at 48117