Note 8 at Eph. 3:7: True ministers are MADE, not self appointed. How are they made? It's according to God's gift. There are some things that we CAN'T DO. We can't call ourselves into the ministry or chose what gifts we operate in (1 Cor. 12:11). We have to be called and anointed of God.

Once we have received God's call and anointing for service, there are things that we can and MUST DO. We have to labor to receive the full benefit of God's grace and calling. But the labor is not to obtain God's call and anointing. That has to come first as a gift. Then we labor against our flesh so that we can let God's gift flow through us unhindered (see note 19 at 1 Cor. 15:10, p. 956).