"God, after He spoke long ago to the fathers in the prophets in many portions and in many ways, in these last days has spoken to us in His Son, whom He appointed heir of all things, through whom also He made the world." Hebrews 1:1-2 NASB
Christ is the source of revealed Truth - This is in direct contrast to the competing, "would-be" points of greatest influence. We are only truly informed as our source of information (what is the bias, the frame of reference, the limitations of our sources of "truth"?) Our sources of information have control/influence on our priorities, goals and ultimately become agenda-setters for our lives. We are more what we "think" than what we eat. Practically speaking, we are (act/live) the summation of our thoughts/thinking. "For as he thinketh within himself, so is he: Eat and drink, saith he to thee; But his heart is not with thee." Proverbs 23:7 ASV As we control the gate of our mind, so we are. What we "let in" becomes what we are, just as the evil man in this passage is not what he says he is but is truly seen in his thoughts and motives. We are warned in Col. 2:8 of this competition for our minds and thoughts - there will always be those looking to lead us away as if the spoils of war by means of philosophies, empty deceits using the "building blocks" (step-by-step processes) based upon the popular thought processes of the "age" and in contrast to Christ.
God spoke by varying means to the Jewish ancestors through the prophets . It is key to note that God "spoke", He revealed His Truth, reality, priorities, morality and more. As in 1 Peter 1:20-21, God directly communicates His Word by means of these individuals and it was not and will never be under the authority of "private interpretation"! His Word as He meant it is the authority and not any particular take on it. Self must be submissive to and not the dictator of God's Word. Even the wording of verse 1 demonstrates that God 'divvied-up' His word in many portions through varying prophets over the years. The writer is clearly advocating divine inspiration of the Old Testament books.
Now God has spoken in a greater "means" than before; He reveals His truth IN His Son. "A mortal King speaks by his ambassador, not (as the King of kings) in his ambassador. The Son is the last and highest manifestation of God (Mt 21:34,37); not merely a measure, as in the prophets, but the fullness of the Spirit of God dwelling in Him bodily (John 1:16; 3:34; Col 2:9). Thus he answers the Jewish objection drawn from their prophets." - Jamieson, Fausset, Brown Commentary
Christ is God, as will be covered in verse 8 of this chapter - His authority is to be without question. In a sense, the writings of the prophets are not to be deemed as greater revelation or greater authority than what was given in Christ. This concept is key for us as well: we must be careful in how we 'rank' philosophical influences over that of the Scripture at large. We may respect God's Word as A source of Truth while placing a higher level of importance on personal opinion, popular religious "authorities" of our day(or the past) or any other competitor.
God has spoken this way in the "last days". "In this final dispensation; or in this dispensation under which the affairs of the world will be wound up.. It might be a very long period, bu tit would be the last one; and, so far as the meaning of the phrase is concerned, it might be the longest period, or longer than all the others put together, but still it would be the last one." - Albert Barnes
The wording carries with it the reality that the "age of man" and this world are limited and are headed for a definite end.
God spoke in Christ. Christ as "Son" is placed as possessor/heir of "all things". Christ as "Son" made all "worlds" (literally ages). As clarified in Col. 1:15, "For by him were all things created, that are in heaven and that are on the earth, visible and invisible, whether they be thrones, or dominions, or principalities, or powers: al things were created by him, and for him" (KJV)
The words/message from our Creator should be the most important to us - why would anything else compete? Doesn't it make sense that the goal of the enemy is to keep us from it?
Seeing that Christ is the "heir" of all things, then all things should be seen in their relationship to Him and His glory and purposes. All other views of "all things" are strictly secondary. As a side note, we being in Christ are called "fellow heirs"(Romans 8:17) so a life pursuit of "all things" is futile since what is to be had is ours in our relationship with Christ. Having something just to have it is vain; the true value of something is found in its use and usability.
-Don Lambert- Talking Points - Hebrews