In the book of numbers, Moses complains in the presence of God because he feels tired and burdened by so many responsibilities in front of the people of Israel (Num 11, 10-15). So God's response was to distribute the responsibility among a group of seventy elders chosen to deal with all kinds of issues. The Spirit of God would also descend on them and thus they would share the leadership of Moses. The problem was when that spirit settled on two more elders who had not been invited. This far from bothering Moses made him happy, because he understood that God's gifts are for the good of all, not to be jealously guarded by a few.
In the Gospel of Mark we find a situation very similar to the situation of Moses and the elders. When some who were not from the group of twelve began to cast out demons in the name of Jesus. The first reaction of the disciples is to forbid it, but Jesus does not think like them, Jesus teaches his disciples to appreciate the good done by others, whoever they are, and never to scandalize, avoiding sin at all costs.
As Christians, many times we disqualify others, those who are not from our group or from our Church, forgetting that we are not masters of the Holy Spirit, nor of doing good works. We should have a more open mind, avoid criticizing and judging others and look for ways to collaborate in building a better world.