# I could no longer stand it

Paul was describing his own emotions by using an idiom. AT: "I could not longer wait patiently" (See: [[rc://en/ta/man/translate/figs-idiom]])

# I sent

It is implied that Paul sent Timothy. This can be made explicit. AT: "I sent Timothy" (See: [[rc://en/ta/man/translate/figs-explicit]])

# our labor

"our hard work among you" or "our teaching among you"

# in vain

"useless"