I would guess he is not teaching due to a mutual decision and other things scheduled into his life. Another person might have asked to lead the group. In small churches, leaders are often not paid, or given a small stipend. Full ministry is too much to take on if they have personal bills to pay.
I suspect that God's view of church structure is a lot more flexible than we make it appear.
The Bible does not contain a lot of structural mandates on how ministry should be carried out. There are references to how things happened, and I think God's desire is that we all do
something.
We have the early instructions for
priests, who did everything from medical to legal mediation, which was carried out for many years. They were chosen by family, not by spiritual depth or theology degree or personality type.
We have reference to split roles in Ephesians 4:11 and I Corinthians 12...
"grace was given to each one of us according to the measure of Christs gift. ... When he ascended on high he led a host of captives, and he gave gifts to men.
11 And he [Christ gave, to the church] gave the apostles, the prophets, the evangelists, the shepherds and teachers, to equip the saints for the work of ministry, for building up the body of Christ
Implying all the saints are carrying out some form of ministry.
We are all the church, as defined in other areas of scripture. The gifts were not given by HR contract. The purpose was not to build up the tip of they pyramid, but to equip the whole corporate body.
Judaism and Christianity have always been theocratic at the core: we all answer to God.
This verse was not a structural mandate, but a description of how Christ's blessing and equipping can build up the church. If we add too much legalism to the statement, we miss the point.
Acts 12 mentions Philip as an evangelist, but it could easily just be a description of what he has chosen to do.
Ephesians 2:20 the church is "built on the foundation of the apostles and prophets, with Christ Jesus Himself as the chief cornerstone.
Acts 20:17 Now from Miletus he sent to Ephesus and called the elders of the church to come to him.
28 "Pay careful attention to yourselves and to all the flock, in which the Holy Spirit has made you overseers, to care for the church of God, which he obtained with his own blood. "
Elders were elected or appointed:
I Timothy 3:1, Titus 1:5, Acts 14:23, Acts 20
Risks of bad leadership:
II Peter 2:1, II Thessalonians 2:3,I Timothy 4:1
And we have Jesus' instructions for
all of us to go into the world baptising and more, speaking of the good news that the kingdom of God is at hand, accessible.
Ephesians 4 cont'd.
We are to grow up in every way into him who is the head, into Christ, from whom the whole body, joined and held together by every joint with which it is equipped, when each part is working properly, makes the body grow so that it builds itself up in love.
There's a good listing of scriptural examples here:
Five fold Ministry
