Long ago, at many times and in many ways, God spoke to our fathers by the prophets, but in these last days he has spoken to us by his Son, whom he appointed the heir of all things, through whom also he created the world. (Heb. 1:1-2)
And the Word became flesh and dwelt among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth. (Jn. 1:14)
And we have the prophetic word (προφητικὸν λόγον) more fully confirmed, to which you will do well to pay attention as to a lamp shining in a dark place, until the day dawns and the morning star rises in your hearts, knowing this first of all, that no prophecy of Scripture comes from someone's own interpretation. For no prophecy was ever produced by the will of man, but men spoke from God as they were carried along by the Holy Spirit. (2 Peter 1:19-21)
God reveals Himself to His people. Yet, what is the nature of this revelation? From Hebrews 1:1-2, we can see that God has indeed utilized a variety of ways in times past to reveal Himself and His will, like through theophanies and even the casting of lots (Lev. 16:8, Prob. 16:33). But NOW all God's revelation is found in His Son, and the former ways of revelation have now ceased, as the Westminster Confession of Faith 1.1 so beautifully states as a deduction from this passage.
The only way to get to this revelation of both the "former ways" and the final revelation of Christ however is through the Scriptures, for we would otherwise have no other way to access God's revelation than for it to be recorded for us, since God's revelation is given in history (thus the contrast between the former times in history and the "now" in history). From 2 Peter 1:19-21, we can see that the written revelation that is the prophetic word or Scripture is given to us as a more sure way of revelation, even in comparison to the glory of our Lord's Transfiguration. In other words, written revelation trumps even the most glorious revelatory experiences. The supremacy of the written Word is expressed earlier in redemptive-history in Isaiah 8:20, "To the teaching and to the testimony! If they will not speak according to this word, it is because they have no dawn."
The relation of Christ and the Word is that Christ IS the Word, at least the Word Incarnate. As Christ who is the final revelation reveals God to us as the Word Incarnate (Logos Ensarkos), so the Scriptures which is the God-breathed-out Word (logos theopneustos) reveals what God in Christ reveals. Christ is the ontological revelation of God, and Scripture the epistemological revelation. God is not a schizopreniac, so obviously the two are one and the same revelation, differing only in kind. Whatever Scriptures teaches, Christ teaches, and whatever Christ teaches, Scripture teaches. God does not have two different logoi (words), but one logos (Word). The Word became flesh (Jn. 1:14), the prophetic word (2 Peter 1:19) breathed out (2 Tim. 3:16), are the one and the same Word.
We do not live in the "former times" of the Old Testament, or even the foundation times of the New Testament. We live in the "last days" where God's revelation is found in Christ and thus in Scripture, the written prophetic word. Scripture is thus the only revelation for us from God today; it is sufficient for us. Therefore, since Scripture is sufficient, it must be clear for us to understand since God intends His revelation to be understood.
Since Scripture is sufficient and clear, therefore any theory that concludes that Scripture is unclear (because of the limits of language or other such arguments) must be in error. This is the argument form known as modus tollens (If p, then not q; q, therefore not p). It doesn't matter how sounds the other theory is. For if the theory (p) will result in a denial of what we already know, the "conclusion" that Scripture is sufficient and clear (not q), then our knowing from Scripture that Scripture is indeed sufficient and clear (q) necessitates a rejection of the theory no matter how true that theory (p) sound to us. The question to be asked for someone who doubts is not whether any particular theory (p1, p2, p3) (that would lead us to conclude that Scripture is unclear) is true, but rather whether the conclusion q is true. If the conclusion q is true, then those theories (p1, p2, p3 etc.) are rendered false by default.
On the other hand, some may ask concerning natural revelation. The biblical answer in Romans 1:18-23 is that there is indeed a natural revelation, yet by itself it only leads to condemnation. Can one grow "close" to God through nature? The Psalmist certainly broke out in praise after seeing the work of God in creation (Ps. 19:1-4) so in this sense we can say that one can "grow close" to God through nature, yet such is done through the lens of Scripture, for we read in Romans 1:18-23 that natural revelation in itself leads the sinner to idolatry and rejection of God. So yes, there is a natural, or general, revelation by God outside of Scripture, yet (1) it reveals only condemnation, (2) in itself it cannot reveal God in grace to us and thus will not bring us to praise Him and fellowship with Him. The Psalmist is only able to write Psalms 19 out of a regenerate heart already in communion with God, something only God can accomplish through His Word. Therefore, while there is a revelation of God outside of Scripture, it is limited and unable to reveal God in grace to us.
God reveals to us, in a way for our good, in Scripture. We are to look at Scripture therefore for our knowledge of God in order to know Him, and even to Scripture in order for us to interpret Nature and General Revelation alright. Above all, Scripture reigns supreme as the source and final authority for our faith, and where we should go to to have communion with God (alongside the sacraments, which are another form of the Word, but those are dependent on Scripture and are another topic altogether).