Evangelicals have been doing great work on this issue in recent years--most significantly and famously the reference work, Commentary on the New Testament Use of the Old Testament (ed. Beale and Carson). But surprisingly, there really aren't many solid books on this issue at an understandable, introductory level. (One of the few, and still worth reading, is S. Lewis Johnson's out-of-print book, The Old Testament in the New: An Argument for Biblical Inspiration, written in 1980.)
Nicole's essay is also still worth reading, and serves as a helpful primer. It's divided in three parts:
1. Range of OT ReferencesIn the third section he takes up the issue of the form of the quotations. He suggests several principles--recognizing that not all of them apply in all cases. But he expresses his view that either singly or in combination, "they provide a very satisfactory explanation of apparent discrepancies in almost all cases, and a possible solution in all cases." Here's an outline of his points:
2. Authority of OT References
3. Accuracy of OT References
1. The New Testament writers had to translate their quotations.
2. The New Testament writers did not have the same rules for quotations as are nowadays enforced in works of a scientific character.a. They did not have any quotation marks, and thus it is not always possible to ascertain the exact beginning, or the real extent of quotations. . . .3. The New Testament writers sometimes paraphrased their quotations.
b. They did not have any ellipsis marks. . . .
c. They did not have any brackets to indicate editorial comments introduced in the quotation. . . .
d. They did not have any footnote references by which to differentiate quotations from various sources. . . .a. Under this heading we might first mention certain cases where we find a free translation of the Hebrew rather than a real paraphrase. . . .4. The New Testament writers often simply alluded to Old Testament passages without intending to quote them. It was quite natural that people nurtured and steeped in the oracles of God should instinctively use forms of language and turns of thought reminiscent of Old Testament Scripture.
b. Slight modifications, such as a change of pronouns, a substitution of a noun for a pronoun or vice versa, transformations in the person, the tense, the mood or the voice of verbs, are sometimes introduced in order to better suit the connection in the New Testament. . . .
c. There are cases in which the New Testament writers obviously forsake the actual tenor of the Old Testament passage in order to manifest more clearly in what sense they were construing it. . . . .
d. In certain cases the New Testament writers do not refer to a single passage, but rather summarize the general teaching of the canonical books on certain subjects in phrasing appropriate to the New Testament, although as to the essential thought they express indebtedness to, or agreement with, the Old Testament. . . . .
e. Finally, we must consider the possibility that the writers of the New Testament, writing or speaking for people well acquainted with the Old, may in certain cases have intended simply to refer their readers or hearers to a well-known passage of Scripture. . . .a. Only a quotation which immediately follows such a formula is to be certainly considered as a formal citation. . . .5. The New Testament authors sometimes recorded quotations made by others. Not all quotations in the New Testament are introduced by the writers themselves for the purpose of illustrating their narrative or bolstering their argument. Sometimes they record quotations made by the personalities who appear in the history, as by Jesus, Paul, Peter, James, Stephen, the Jews, and Satan. . . .
b. Even when a definite formula points directly to an Old Testament passage, we may not expect strict adherence to the letter of the source when this quotation is recorded in indirect rather than in direct discourse. In such cases we often find remarkable verbal accuracy, but we cannot criticize departure from the original when the very form of the sentence so naturally allows for it.
c. When what may appear to be a citation is introduced by a form of the verbs “say” or “speak,” it is not always certain that the writer actually intended to quote. Rather, the possibility must at times be taken into consideration that we are facing an informal reference to some saying recorded in Scripture. . . .