'Confirming' in the Bible

And they went out and preached everywhere, while the Lord was working with them and confirming the word by the signs that followed.]

For I tell you that Christ has become a servant and a minister to the circumcision (Jews) on behalf of God’s truth, to confirm and verify the promises made to the fathers,

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].