More good advice from Dr. Luther:
It's good to let prayer be the first thing you do in the morning and the last thing you do at night. Be on guard against false, deceitful thoughts that say, "Wait awhile; you can pray in an hour First, you must finish this or that." For with such thoughts, you turn away from prayer toward the business at hand, which surrounds you and holds you back so that you never get around to praying that day.
Of course, some tasks are as good as or better than prayer, especially during an emergency. Nevertheless, we should pray continually. Christ says to keep on asking, seeking, and knocking (Lk 11.9-11). And Paul says that we should never stop praying (1 Th 5.17). Likewise, we should continually guard against sin and wrongdoing, which can't happen if we don't fear God and keep his commandments in mind at all times. In Psalm 1 we read about the one who is blessed: "His delight is in the law of the LORD, and on his law he mediates day and night" (v.2).
We shouldn't neglect the habit of true prayer and get caught up in necessary work--which usually isn't all that necessary anyway. We can end up becoming lazy about prayer, cold toward it, and tired of it, but the devil doesn't get lazy around us.
(from Faith Alone: A Daily Devotional / LW 43:193)