“Spiritualizing involves turning the physical realities of a biblical text into unwarranted spiritual analogies and applications. When preaching about Jesus calming the storm on Galilee, for example, a preacher might say, ‘This storm represents the storms that we often face on the sea of life.’ Or, when discussing the Israelites' seven-circuit march around the walls of Jericho, he might spiritualize the event by listing seven acts of obedience in response to which God will remove the obstacles that stand in our way. When preaching about God's parting the Red Sea, he might spiritualize the text by saying, ‘The Red Sea represents the difficulties in your life. This text teaches that God will carve a path straight through them.’
When we spiritualize the details of a text, we divorce that text from the original author's meaning and purpose. We snatch the authority from the inspired pen of the biblical writer and invest it in our own imaginations. Though the advice we give and applications we make may provide help to our listeners, we inadvertently put words into God’s mouth that He never spoke. We attach a ‘thus saith the Lord’ to an application that would cause the original writer to scratch his head.”
Daniel Overdorf, Applying the Sermon: How to Balance Biblical Integrity and Cultural Relevance (Grand Rapids: Kregel, 2009), 74-5.