The prohibition to take food, a bag, money, and extra clothing implied that the disciples had to trust God alone to provide for them what is necessary. God not only provided the authority (Mark 6:7) necessary for them to do the work of God’s kingdom, but he also wanted to teach them dependence on God alone for all their temporal necessities.
The bag could refer to a beggar’s bag. Begging was common in the time of Christ. The disciples were not to beg. In any case they were not to have a bag with them, implying that they should not have taken anything with them.
The extra tunic may refer to a type of coat that could double as a blanket.1
These barest of supplies should have taught them that true disciples of Jesus should be dependent on him alone. They should have been willing to go wherever Jesus sent them despite the circumstances or lurking shortcomings. If they went in this manner, they were to be sure to go in faith.2
The Twelve had to travel light, depending on God’s provision for clothing, food, and lodging.
8 He charged them to take nothing for their journey except a staff no bread, no bag, no money in their belts