Luke 10:4

Carry neither purse (provide neither gold, nor silver, nor brass in your purse, S. Matt. x.) nor scrip. Neither purse for money, nor scrip for food; for the Shepherd will supply both if needful. He commands them to look to Him who sent them forth for the necessaries of life. Euthymius.

For the preacher ought to have such trust in God, that although unprovided with the expenses of their present life, he should be convinced that they will not fail him; lest whilst his mind is taken up with things temporal, he should be less mindful of things eternal. S. Gregory. See S. Matt. x. For Christ here gives to the seventy disciples the same commands which He before gave to His twelve apostles.

And salute no man by the way. Do not turn aside to salute your friends or to commune with your acquaintances, but, avoid all such delays, and devote yourselves entirely to the preaching of My gospel. SS. Augustine, Ambrose, Gregory and others

But on the other hand, Euthymius says, Christ means not that His disciples should uncourteously refuse a passing salutation. He only forbids those formal greetings, * which are hindrances to the ministry, and causes of offence. So writes S. Ambrose, who here alludes to the command of Elijah, "If thou meet any man, salute him not; and if any salute thee, answer him now again" (2Ki 4:29): a command given lest Gehazi might enter into converse with some one by the way, and thus be forgetful of the duty he was sent to perform.