No one should claim to be a preacher without being born-again, when I talk about preacher here, it can be pastors, evenglists, apostles, prophets, bishops, etc
Matthew 7:17 Even so every good tree bringeth forth good fruit; but a corrupt tree bringeth forth evil fruit.
7:18 A good tree cannot bring forth evil fruit, neither can a corrupt tree bring forth good fruit.
Before anyone will ever take up the Mantle of preaching the gospel, he must first of all have the new born experience, in order to be get others converted. There is no way that an unsaved preacher will be able to give a sound converting message to his congregation, that will really bring about salvation of souls; since what is in him is not empowered by the Holy Ghost. When I talk about Salvation: it is an open door to sanctification, Holy Ghost baptism, Spirit filling, anointing and God's power for effective gospel. Therefore if any one is not saved he cannot experience other spiritual blessings that come after salvation. That is the reason there is a great need for every preacher to be born-again first, before taking the responsibility of preaching the gospel.
This will give him a better ground in minding about the salvation of other.