"Reading the notations in my Bible, I noticed that Hebrews 2.7 is a so-called quote of Psalm 8.5. And yet, when I read the two verses they're quite different. Why?"
The verses in question read: "You have made them [humans] for a little while lower than the angels; you have crowned them with glory and honor" (Hebrews 2.7). And Psalm 8 reads, "You have made them [humans] a little lower than God, and crowned them with glory and honor" (Psalm 8.5). The primary difference between the verses is in the phrase where humans are a little lower that "angels" as cited in Hebrews or a little lower than "God" in Psalms. The difference is significant.
On the other hand, the difference is not surprising for two reasons. The first is that the writer of Hebrews knew up front he wasn't likely to get the quote right especially since he was quoting from memory. In Hebrews 2.6 we read, "But someone has testified somewhere. . . ." This is clearly not the writing of one who is about to cite a primary source for a term paper, rather the writer was intent on getting a point across in his letter. Accuracy wasn't the prime con- sideration, support for his point was.
Still, there is a great deal of difference between saying we're just a little lower than God as opposed to being a little lower than the angels. This is one point you wouldn't think he'd get wrong. But he did. Why?
Because the writer wasn't quoting the original, but a translation.
During the time of the early church the scriptures had already been translated from Hebrew into the legal language of the people Greek. In about 275 BCE in Alexandria, Egypt 70 translators translated the Hebrew scriptures (the Old Testament) into Greek. The resultant edition was called the Septuagint, meaning 70, in honor and recognition of the 70 translators. This translation was used nearly exclusively by the Jews until 70 CE, but continued to have wide acceptance by the Christians for many years.
But even poor translators know the difference between the word for God and the word for angels how is it these translators got the translation wrong?
Because translations are always culturally biased, and the Septuagint was no different. During the time in which the Septuagint was translated the prevailing notion in the faith was that angels were superior to humans, not unlike our society's understanding of heavenly beings today. Further, there was a prevalent teaching that humans were terribly sinful and tainted and any comparison to God was unthinkable. So, even though the original Hebrew in Psalm 8.5 clearly read elohim, God, the translators took the liberty to use the Greek word angelos, angels, as their translation's choice. Indeed, the King James wrongly translates it this way as well, thus supporting the traditions of the Septuagint as opposed to using correct translation practices.
Every biblical translation reflects the culture in which they are written. Idioms and metaphors in scripture are often changed to help the reader make sense of the passages. Indeed, there are numerous passages that make little sense to modern readers when translated directly, so translators use words, phrases, and idioms that help the reader understand. In this case, the thought that humans were so highly placed by the psalmist was offensive to society, and so the translators took liberties with the text.
In any event, by the time the writer of Hebrews set pen to papyri, the words of Psalm 8 had been significantly changed from the original. So, although this quotation of the psalmist in Hebrews is erroneous today, those of his readers familiar with the Greek translation would instead have applauded his memory.