If the one who is walking in the Spirit is supporting the local Christian community, how was that community supposed to use the support?
“Doing good” might refer to doing things that were considered a civic virtue in the community. In a Jewish context “doing good” might refer to giving to the poor, protecting the widow and orphan, even burying the dead. Since the theme of giving money is prominent in this chapter, it is possible Paul’s command here was applied to a community fund which was collected and distributed to those in need. How did the early church distribute funds?
Paul warns his readers not to become weary in doing these acts of goodness. The phrase appears in 2 Thessalonians 3:13. The word Paul uses here (ἐγκακέω) sometimes refers to discouragement, or losing heart, perhaps even afraid. The final phrase uses another verb (ἐκλύω) which refers to being exhausted or worn out. It appears in several military contexts to indicate losing one’s nerve. Why would someone become discouraged or afraid of doing good deeds?
One option is that there is no response from those that are helped. To extend the sowing and reaping metaphor, if a farmer sowed seed in a field and nothing ever grew, he might give up sowing that particular field. If you volunteer at a homeless shelter, you can do many good things for people. But there might be little or no response from the people you are trying to help. That can be very discouraging!
A second option is that someone in Paul’s churches was afraid to do good works such as helping the poor in a community where helping the poor was not considered a virtue. Early Christians often helped people who were very sick, even when their lives were a risk. It is possible that this is a real fear people felt when doing acts of mercy.
A third option is that people who are busy doing good do in fact get tired of the work. Paul may very well have in mind physical exhaustion from serving people in the community! This is a danger in any kind of service, but it if someone is serving in a ministry where they are working hard and never see any results, they naturally become discouraged.
The fact that Paul includes a condition in verse 9 (if we do not give up) is an indication that the harvest or reward does not happen automatically (Witherington, Galatians, 433). It is hard work to be a member of God’s family, but it is ultimately rewarding.
Doing good begins with the “household of faith” and moves outward to everyone else. This may be people in need within the household of God because they have a burden they cannot bear. It also includes those who have been called by God to teach the Scripture in the local church.