Great topic,
Erin Joy!
First, to address your specific question: no, a pastor need not have the fivefold ministry, and probably will not, to be ordained. What he does need is
one of the gifts, and the humility to recognize what he does not have, and to allow the raising up from the congregation those who will serve in the roles he is not equipped for.
Scriptural justification:
And God has appointed these in the church: first apostles, second prophets, third teachers, after that miracles, then gifts of healings, helps (diakonoi), administrations, varieties of tongues.
Are all apostles? Are all prophets? Are all teachers? Are all workers of miracles? Do all have gifts of healings? Do all speak with tongues? Do all interpret? (I Cor. 12:28-30)
Paul obviously expects a "No" answer to the series of questions. To cite an example from my own experience, the rector (chief pastor) of a church we were members of for 20 years was a brilliant administrator and excellent preacher and teacher, but horrible at the pastoral-counseling ministry -- and wise enough to realize this, and so caused the church to call an outstanding clergyman as his "pastoral associate" with the specific task of handling pastoral visitation and counseling, which he was excellent at. That man was poor at administration and mediocre at preaching, and so had had difficulty at being called to churches on his own, but was one of the most gifted persons I've ever met at one-on-one ministry. And they fit together as a spectacularly good team, until the rector took ill and retired.
But there is a deeper question, and one singularly important to the ordained ministry: what constitutes a valid calling?
I would suggest that there are three necessary steps, none of which can be omitted:
1. The person seeking ordination must feel himself called by the Holy Spirit to the ordained ministry.
2. Those in authority over the church must put him through a discernment process to assure themselves that his calling is indeed valid, and then arrange for his training in the skills which he will need to be an effective minister.
Two comments are in order here: There is no way for an individual to himself distinguish between a true call by the Holy Spirit and his own ego deceiving him. The discernment process is to validate the call, not to exclude those truly called for secular political reasons, as unfortunately sometimes happens. Second, it is very rare for a person to have the natural gifts that equip him for immediate ordination, and even these can be honed. Preaching a good sermon is a learned art, homiletics, and the minister-to-be must be equipped to be able to read the Scriptures in the original languages and explicate them to those under his care as a teacher. He must understand thoroughly the doctrines of his church and why they are important. And he must be equipped in the skills necessary for pastoral care of his congregation. None of thse
require a seminary education, but that is the mode prescribed by most churches as the effective way to get a concentrated background in them all.
3. He must be formally commissioned to the ministry which he is to undertake by those empowered to do so.
In my own church, which adheres to the Apostolic Successoion, proclaiming the Word of God officially with the authority of the Church and ministering the Sacraments are gifts transmitted by the laying on of hands with prayer by the bishops, who received it from the bishops preceding them, on back to the apostles and Christ Himself. My own name on these boards reflects my patron saint, whom I try to emulate, who was ordained as the Bishop of Smyrna by John the Beloved Discple, and from whom I can trace a direct lineage through Theodore of Tarsus and William White to Ned Cole, who laid hands on me to confirm me with the gifts of the Holy Spirit in my ministry as a layman.
In other churches, of course, the commissioning may be done by the local church, through its leadership, or by the pastors of neighboring churches. But the new minister must undertake vows to do the work to which he is called and be formally set apart to that work by those who are so designated to do that setting apart.
Skip any one of these steps, and trouble is in the offing. Self-appointed men will undertake ministries to which they have not been called. Men not called will be passed for ordination. Untrained men will do a poor job of ministry. And people will fail to keep vows which they have not made, and have no accountability for their ministry.