Reading the scriptures as a preacher presents unique challenges. As a preacher, we stand in a different place vis-a-vis the text than others, because our reading is often in the service of something else. We read in order to preach on what we read. We read instrumentally, if you will.
One danger is that we can get into the habit of thinking we read the text for others, or on behalf of others, rather than for ourselves. Instead of asking, "What is God saying to me through this text?" we ask, "What is this text supposed to say to the people I'm preaching to on Sunday mornings?" This is a very dangerous habitus, because we come under the illusion that we are only reading the bible for others, and it isn't addressing us. As if God would speak through us and not to us.
The only way to avoid this danger is for the preacher to read the bible other than for preaching, for other purposes, and to do it very, very regularly. So preachers should develop what I think of as a threefold reading of Scripture. It would look like this:
1. Read the bible for personal devotions (following some plan, like a devotional guide, Moravian Daily Prayer, daily prayer office, etc.--these would be shorter meditative passages read for the life of prayer)
2. Read the bible for study and development (possibly with a companion like a commentary, or in company with others, like a small group bible study--these would be longer passages of Scripture, read for the sake of deepening in the biblical story)
3. Read the bible for preaching and teaching (this would be the instrumental mode, reading in preparation for our weekly work, like classes we are teaching or sermons we are preparing)
These should also be prioritized in this order. The devotional should have highest priority, the study second priority, and the preaching and teaching mode third. I know this inverts the normal mode most of us probably engage in (the pressure of the next sermon can sometimes overwhelm us and keep us from the first two), but we should keep this order in mind and strive for it. And again, this is important not as an abstract rule, but because the preacher needs to lead out of who they are, and if we are inviting our congregations to read the bible devotionally, and engage in personal study or small group work, we should be the first out of the gates. Not to mention the fact that we need the first two for our own growth in faith, and we need the first two in order to do the third well in any event.