This is a passive sentence which can be translated as, "Therefore the church sent Paul, Barnabas, and some other believers from Antioch to Jerusalem. They passed... ." (See: [[rc://en/ta/man/translate/figs-activepassive]]) (see: [[rc://en/ta/man/translate/figs-explicit]])
The words used for "passed through" and "announced" indicate they spent some time in different places sharing in detail what God was doing.
## the conversion of the Gentiles ##
Many Gentiles changed their belief from the Greek & Roman gods to believing in Jesus.
## they were welcomed by the church and... ##
This is a passive construction that can be translated as "The church members welcomed them including..." (See: [[rc://en/ta/man/translate/figs-activepassive]])