In his book Reaching the Nations Mike Frisby helps churches work with people who are engaged in cross-cultural mission. After having profiled the personnel and clarified the call, Mike recommends researching the route.
In this section Mike helps the prospective worker think through issues such as short or long-term service, what additional ministry training is needed, what cross-cultural training is required, what additional life-skills would be helpful and learning where necessary a new language.
In addition Mike reminds us that we need cross-cultural workers to be well grounded in the Word of God.
It is essential that all those involved in seeking to reach people from another culture be well grounded in the scriptures. They should have a good grasp of the principles of interpretation of scripture (hermeneutics) and proven ability in applying the scriptures to their everyday lives. We are looking for self-feeders who love the word of God and are seeking to be obedient to its teaching. (See 2 Timothy 2:15)
The level of biblical competency required will depend largely on the sphere of future ministry activity. Has the person attained a sufficient level of biblical competency? Could they benefit from further training? Are there suitable training options within your own local church or region?
It can also be helpful to ascertain whether or not there are specific subjects or areas of doctrine or practice that are relevant to their intended sphere of service. (For example justice; suffering; restitution; sovereignty of God; Spiritism; idolatry; family life; singleness; ancestors; angels; demons; etc.)
You can get the book here