Matthew Henry on Mark 6:7-13

Though the apostles were conscious to themselves of great weakness, and expected no wordly advantage, yet, in obedience to their Master, and in dependence upon his strength, they went out. They did not amuse people with curious matters, but told them they must repent of their sins, and turn to God. The servants of Christ may hope to turn many from darkness unto God, and to heal souls by the power of the Holy Ghost.