Romans 4:17

(As it is written, A father of many nations have I made thee) before him whom he believed, even God, who giveth life to the dead, and calleth the things that are not, as though they were.

Upon the occasion of God's making the land covenant, sealed by circumcision, with Abraham, God made mention of another covenant previously made with Abraham, and used the past tense to show that the previous covenant had nothing to do with the covenant of land and circumcision about to be made. Paul's introduction of the quotation from Genesis 17:5, included in parenthesis in this verse, and especially God's use of the past tense, "have I made thee," proves that the previous covenant was distinct from the land covenant about to be made in the immediate future, and also indicated that the previous covenant (the great promise) was fulfilled by,Christ the Saviour of the world.

The law of Moses, which the Judaizing teachers were so zealously seeking to fasten upon Gentile Christians, has nothing to do with the promise, or covenant, to make Abraham the father of a multitude of nations.[14]

The last two clauses of this verse refer to Isaac's being born to Abraham and Sarah, contrary to nature, when both the parents were of advanced age, and "as good as dead" (Hebrews 11:12).

A father of many nations have I made thee ... At the time God said these words to Abraham, the birth of Isaac was still far in the future, and those "many nations" existed only as a promise of God; but God had promised them and, therefore, did not hesitate to speak of them as already born. This is prophetic tense, in which God speaks of the future as though it were past, and in which, also, God's prophets, speaking in his name, foretell future events.