. . . A Sabbath days journey? (vs. 12) - a half a mile or so. Why the interest in mileage? These events are located in and around Jerusalem.
Why Jerusalem? . . . (vs. 1:4, 12 note also Luke 24:52-53) - For Luke, Jerusalem is theologically important: in Jerusalem Gods prophet meets his death (Lk. 13:33), the nascent messianic community is born, and from Jerusalem the kingdom of God would emanate to the ends of the earth.
Absence . . . (vs. 9-11) - Jesus has departed. Absence. The disciples, however, are still very much present and will continue to live on the earth-with persecutions and natural limitations-but yet equipped by the Spirit.
Christs journey into heaven becomes the churchs journey into the world--the churchs mission is propelled by the reality of the returning Christ. During our mission to the end of the earth, we are comforted by him who has ascended into heaven. He is still present in Word and in Spirit. 
We live in the "in-between" time following Jesus ascension and before his return. Both of those events can influence us toward faithful living. However, the text requires us to come to terms with the Spirit. Faithful living requires this quality of Gods life-the Holy Spirit-to enable us to be obedient and faithful.
eugene peterson: "Waiting . . . means going about our assigned tasks, confident that God will provide the meaning and the conclusions. It is not compelled to work away at keeping up appearances with a bogus spirituality." [ED-a useful thought in light of the in-between time that our lesson suggests.]
Block #1: Describe the heated debate surrounding church as being irrelevant and the temptation to "market" the church to better "sell" the gospel. 
Block #2: Suggest that cultural relevancy combined with faithfulness may not always be met with open arms; note the life and teaching of Jesus and what happened throughout Acts to the apostles.
Block #3: Amidst the undulations of style, trend, and social change, the Christian community is called to hold what the Lord "taught from the beginning." Confession: we havent always done that very well! In our lesson, we have reluctant disciples-especially in taking the gospel to the ends of the earth. The progress of the gospel is not always smooth, but au contraire, characterized by reluctance and persecutions.
Block #4 Illustration: a disaster off rocky coast in Canada. The fishermen build a rescue station with emergency equipment. Over the years more and more comforts added-TVs, innerspring mattresses, central heating. Enter: another shipwreck; everyone on duty sleeps through; no one is saved.
Block #5: What will keep us on track in our call to be faithful witnesses? Jesus promises the Holy Spirit-in the Spirits control, crisis becomes opportunity!
 B.A. Muller in Sermon Guides for Preaching in Easter, Ascension, and Pentecost (Grand Rapids: Wm. B. Eerdmans Publishing Company, 1988), page 111.
This homiletic form is adapted from B.A. Muller, pp. 114-116.