The apostle Paul and Barnabas were commissioned and sent out by a local church. (Acts 13:1-4) Before they were approved of and sent out, they were serving in the local church. (Acts 11:26) Paul exhorted the church at Rome that they are also called to Christ, (Romans 1:5 – “you also are the called” – as Paul says, “we were called to be apostles”, 1:1-4) In Romans 10:13-15 and 15:20-21 and 16:25-27 ; these are all basically exhortations to the local church at Rome to share and own the vision and passion that the apostle Paul has. A church cannot do everything or support every good missionary, and some churches have more or less capacity to be involved depending on the resources and giftings that God has sovereignly appointed for them. Every local church should have a vision for some kind of outreach, both in local evangelism and missions. (Matthew 28:18-20; Acts 1:8; Luke 24:44-49) And the leaders / elders/ pastors should be praying and seeking for opportunities to support Biblical missionaries and to encourage young qualified believers to explore missionary service.
When a local church does support some missionaries, there should be regular times of prayer, information sharing (emails, letters, photos, etc.) and teaching times, and allowing the missionaries to share/ teach/preach/report when they are home.