Is it possible to change an old group into a Glad Tidings one?
It is possible but not very easy. The older the group and its participants, the more difficult it is to change. Rather than trying to change the old ones, start new.
When should you start?
After an evangelistic campaign is a good time to start, but you should also recommend Glad Tidings groups to new people who come to your weekly services and other meetings.
The ideal size of a group is 4-8 people
If two Christians invite their two friends, you already have a group of four ready. When the number of participants exceeds 8 persons, you must absolutely divide it in two. If you don't, the group stops growing. If you do, both halves go on growing.
Length and intervals
One study session shouldn't take more than one hour, or one hour and a quarter at the most. If the study drags on, participants become tired and tend to stop coming. A group can gather anywhere from once a week to once a month. You can also hold a Glad Tidings group limited number of times: one semester, ten times etc.
A house. It is better that someone other than the owner of the house leads the
A leader. It helps greatly if the leader has participated in a Glad Tidings training course (or at the very least heard the cassettes of the course).
Participants. In an ideal situation, half of the participants are Christians, and half are non-Christians, but you can conduct a Glad Tidings group even if the situation is not that ideal. You can invite any person from 10-100 years of age. There is only one exception: don't invite Christians who you know talk too much. Other types of meetings are more suitable for them.
Bibles. Everybody must have a Bible or a copy of the text in hand. Take copies if you suspect that some people will come without bringing a Bible. The easiest translation for non-Christians should be preferred for these studies.
A Glad Tidings Bible study guide. Glad Tidings Bible studies are based on questions, which should be neither too difficult nor too easy for Christians and non-Christians alike. There is one book written by Mailis Janatuinen with questions for each of the four gospels (see the last page).
Serving tea etc. Make sure that people feel free to leave after the actual study. A simple teatime is for those who have time available. A meal should be offered only before Christmas or on other special occasions.