“Not that we are competent in ourselves to claim anything for ourselves, but our competence comes from God.” (2 Corinthians 3:5)
Competence refers to the state of having the required skill set and being suitable for a particular task. It is therefore task-specific. Being competent in a particular role doesn’t automatically make you competent for a different role unless you have been specifically equipped for that role as well.
Here, the famous Apostle Paul, after describing the church in Corinth as being the result of their (together with Timothy) ministry, was quick to add that their competence was from God.
Competence to be a banker may come from an educational institution. Competence to be a carpenter may come from a carpentry shop. But competence to do the work of God comes from God.
This explains why after Jesus commissioned His disciples, He told them to wait until they receive the promise of the Father. At last, on the day of Pentecost, they were empowered for service.
Beloved, in all that you attempt to do for the Lord, be careful to continually seek His grace and strength for without Him, we can do nothing, and through Him we can do all things.