"The grass withers and the flowers fall, but the word of our God stands forever." While everything else exists for a specific time, God's counsel is for all time. As people who are called to live according to His principles, we open a dangerous can of worms by saying that a portion of His Word is no longer applicable. Once we permit person "A" to identify one portion of Scripture as "dated," there is nothing to prevent person "B" from identifying another portion of Scripture as "dated." Such a practice would render the entirety of God's Word "up for grabs," and make it meaningless. Contrary to this view of Scripture is God's view as stated here by the prophet Isaiah: It's all true and it's all authoritative, and it is impossible for any of it to "fade" or become "dated" in its applicability.
The message from Isaiah is that our "deliverance" comes from the exact place our "wisdom" comes from, and if we attempt to detract from God's wisdom, we are also detracting from his message of salvation. The only way for anyone to have salvation is to worship the triune God of Scripture, and the only way to correctly worship Him is to live according to His revealed and inerrant wisdom. Simply put, dependence upon any other "word" will lead to our destruction. A psalmist writes about God's Word being "settled in heaven," meaning in God's secret counsels. It is eternal, just as is God, and its promises will be fulfilled at just the right time. It is our shield and our only sure foundation.