Most excellent (kratistwi). See on "Lu 1:3" to Theophilus though not in Acts 1:1 . It is usual in addressing men of rank as here, like our "Your Excellency" in Acts 24:3 and Paul uses it to Festus in Acts 26:25 . Greeting (cairein). Absolute infinitive with independent or absolute nominative (Klaudio Lusia) as is used in letters ( Acts 15:23 ; James 1:1 ) and in countless papyri (Robertson, Grammar, p. 1092).