It is implied that the extent of the power and authority granted Saul was limited to the Jewish people at this point in time. (See: [[rc://en/ta/man/translate/figs-explicit]])
"chosen instrument" refers to something that is set apart for service. AT: "I have chosen him to serve me" (See: [[rc://en/ta/man/translate/figs-metonymy]])
# to carry my name
This is an expression for identifying or speaking out for Jesus. AT: "in order that he might speak about me" (See: [[rc://en/ta/man/translate/figs-metonymy]])
# for the cause of my name
This is an expression meaning "for telling people about me." (See: [[rc://en/ta/man/translate/figs-metonymy]])