Pastors, if you are not following Brian Croft’s “Practical Shepherding” blog, you need to. He consistently has great, relevant content that I think you would find helpful. His latest post is titled, “How Long Should My Sermons Be When I Preach?” And it’s about just what you think it’s about—the length of your sermons. Brian doesn’t mandate a certain length, but rather gives a set of principles to consider. He says that pastor should determine the length of his sermon…
1) Based on where your people are, not where you think they should be.
2) Based on how good and seasoned a preacher you are.
3) To leave your people longing for more, not less.
This is good, wise stuff. Read the rest here.
The basic answer is when the Holy Spirit says it is too long. One minute might be too long in some cases and much longer might be fine in other cases. If you publish a schedule, respect your listeners by keeping to the schedule for the time.