'Apostleship' in the Bible

It is through Him that we have received grace and [our] apostleship to promote obedience to the faith and make disciples for His name’s sake among all the Gentiles,

If I am not [considered] an apostle to others, at least I am one to you; for you are the seal and the certificate and the living evidence of my apostleship in the Lord [confirming and authenticating it].