What is not needed is heavy
That which is not needed is heavy and even it does not imprison you it takes away space and in any case achieves the same aim of evil: reducing movement leading to death.
That is why if one is working in the Church as an apostle or disciple of Christ one must not take anything that is unnecessary for the journey even if the idea goes against our human opinion or convictions.
He instructed them to take nothing for the journey but a walking stick. A walking stick is necessary. It is a sign of God’s support. It is also a sign of the grace of service, not of power. Is food necessary? No. What do you mean, no, no one can live without food. That is true of course but Jesus knows that it is useless to take what you know will be offered to you along the way. You will find food along the way in accordance with the timing and the quantity dictated by divine providence.
A sack? No! It is not necessary. Personal effects are unnecessary, they tie you down, you will be afraid to lose them or that someone will take them away from you. They are unnecessary, a burden, they hold you down, they make you worry, they occupy the mind and the heart.
Money in your belt? No! It is unnecessary, it weighs you down. Money has a specific weight that is higher than lead even if it is paper. Money is very heavy, it keps you from running, or more precisely you will run for it. If it is necessary you will find money or rather you will servem as a go-between for transferring funds for projects, or to help some people, or to improve some situations. But it will be like water when you wash your hands. You use it but then even the smallest drop is dried and you continue on your way. So if money will be necesssary to serve the wellbeing of others the Lord will provide, but without keeping anything in your belt. Two tunics? No. Too heavy. Besides, if you have two tunics in the morning you will be faced with a dilemna of which to put on. If people calculated the time they waste every day deciding what they should put on they would see that it is an unbelievable number of hours.
Sandals? Yes. Sandals defend you from the roughness of the ground, they help to make your journey quicker and more linear.
What is unnecessary is heavy and that which is heavy takes away movement and leads inexorably to death.
His instructions represent a great change in mentality but it is what Jesus asks, what He asks his disciples to announce to the world. It is a powerful, mighty, luminous, powerful change in mentality. And an announcment of this kind cannot of course come from apostles and disciples loaded with sacks, money, tunics. It would be ridiculous and disrespectful. Apostles and disciples who are graceful and light, charged only with the Holy Spirit will thus have the power to vanquish diseases and to drive away demons. They certainly have the spiritual agility to overcome the non-movement of any physical or psichic disease, they have the right amount of space in their heart to collect divine power and grace. Grace that is certainly quicker and more powerful than evil spirits so they can easily drive them away.
They have God's freedom in their heart. What more do they need?