that God has spoken

God, after He spoke long ago to the father in the prophets in many portions and in many ways, in these last days has spoken to us in His Son...(Hebrews 1:1-2)

One of the many unique features of the New Testament book of Hebrews is the constant emphasis on the primacy of God. Moreover, the author articulates a doctrine of God that is unmistakably Trinitarian. A principal manner in which we observe the Triune God dynamically active is in the proposition that God has spoken. It is this proposition to which the writer of Hebrews initially turns in order to comfort the reader, providing assurance with regard to the authority and efficacy of the person and work of Jesus Christ.
Accordingly, the author of the letter to the Hebrews begins the "brief word of exhortation" with the reality that God has spoken (Hebrews 13:22; 1:1-2). This terse, though profound, phrase is a bold claim that related not only to the original hearers, but one that bears upon humanity today with urgent immediacy. That is, (especially considering American Christianity) we live in a time in which we can (and sometimes do) easily take the word of God for granted (consider, for example, the multitude of Bibles readily available to us as well as their accessibility). Yet, perhaps now more than ever, we cannot afford to treat God's word with even the slightest amount of indifference. Before I am misunderstood, I do not intend to mean that we are personally apathetic in our approach to God's word as authoritative for our lives. Rather, the notion that God has spoken can become so commonplace in our Christianity that we fail to understand how this reality impinges upon all of humanity, especially in a society whose prevalent postmodernism is characterized by the question, "Indeed, has God said?" (Genesis 3:1) Accordingly, our lives need to be marked by a complete understanding for ourselves and others that God has spoken, and still speaks to us today.
Christianity is, in part, predicated upon a claim to the validity and tangibility of the proposition that God has spoken. As the writer of Hebrews notes, "God [...] spoke long ago to the fathers" (Hebrews 1:1). Such an action implies initiation (agreeing with God's sovereignty), desire for fellowship through communication (acknowledging His personhood), and continuity between past and present (affirming the accuracy and dependability of His word). Undoubtedly, if we consider that God exists, the most reliable means for humankind to ascertain any knowledge about God is if God reveals God to us. Furthermore, we ought to expect consistency and continuity throughout the history of God's creation. Hebrews, and Christianity, declares the actuality of God's communication to humankind and invites us to consider its meaning for our lives. Indeed, God has spoken in the Scriptures, whose anticipatory nature receives climactic fulfillment in Jesus Christ.