{And thou hast well done that thou art come} (su te kal(9373)
epoi(8873)as paragenomenos). "And thou didst well in coming." A
regular formula for expressing thanks as in  Php 4:14  3Jo 1:6  2Pe 1:19 . The participle completes the idea of kal(9373) poie(935c)
neatly. Cornelius commends Peter for his courage in breaking away
from Jewish custom and takes no offence at the implied
superiority of the Jews over the Gentiles. Cornelius and his
circle of kinsmen and close friends are prepared soil for a new
era in the history of Christianity. The Samaritans were now
nominal Jews and the Ethiopian eunuch was a single case, but here
Peter the chief apostle, not Philip the preaching deacon
(evangelist), was involved. It was a crisis. Cornelius reveals an
open mind for the message of God through Peter. {Commanded thee}
(prostetagmena soi). Perfect passive participle with the dative
case (soi). Cornelius is a military man and he employs a
military term (prostass(935c), old word to command). He is ready for
orders from the Lord.