What does Hebrews 2:6 mean?

To modern eyes and ears, it seems odd to refer to the Scripture as saying something "somewhere." However, the writer of Hebrews is just using flowery language—a turn of phrase the original readers would have recognized naturally. The audience of this letter are Jewish Christians, who are familiar with the Old Testament texts. So this phrasing is a bit like asking modern-day Christians, "doesn't the Bible say somewhere that God loved the world so much He sent His son? (John 3:16)" The "somewhere" phrasing, then, is really a reminder of something in the Scriptures which the readers obviously already know.

Verses 6, 7, and 8 of this passage cite Psalm 8:4–6. This Psalm praises God for using His creation—human beings—to rule the earth, instead of ruling it directly. The main point being made in the Psalm is that people are given great value by God, even though we really don't deserve it. And, not only are we valued, we are also given power and authority, which we likewise don't truly deserve. We're sinners, but God still holds us in a special place.

The writer of Hebrews will apply this idea to Jesus. God created mankind, and gave them power and authority, despite their sin. This means becoming human is not "beneath" God, and Messiah taking on a human form fits the destiny of man: to be in human form but to have authority in creation. This verse, in particular, hinges heavily on the psalmist's use of the term "son of man," which the Jewish people associated with the Promised One (Daniel 7:13–14).