Matthew 4:20

These disciples did not follow Christ from desire of the honour of a doctor, but because they coveted the labour itself; they knew how precious is the soul of man, how pleasant to God is his salvation, and how great its reward. These were their desires, for which they left all and followed; teaching us thereby that none can possess earthly things and perfectly attain to heavenly things.

(Hom. in Evan. v. 1.) Peter and Andrew had seen Christ work no miracle, had heard from him no word of the promise of the eternal reward, yet at this single bidding of the Lord they forgot all that they had seemed to possess, and straightway left their nets, and followed Him. In which deed we ought rather to consider their wills than the amount of their property. He leaves much who keeps nothing for himself, he parts with much, who with his possessions renounces his lusts. Those who followed Christ gave up enough to be coveted by those who did not follow. Our outward goods, however small, are enough for the Lord; He does not weigh the sacrifice by how much is offered, but out of how much it is offered. The kingdom of God is not to be valued at a certain price, but whatever a man has, much or little, is equally available.

But mark both their faith, and their obedience. For though they were in the midst of their work (and ye know how greedy a thing fishing is), when they heard His command they delayed not, they procrastinated not, they said not, "let us return home, and converse with our kinsfolk," but "they forsook all and followed," even as Elisha did to Elijah. Because such is the obedience which Christ seeks of us, as that we delay not even a moment of time, though something absolutely most needful should vehemently press on us. Wherefore also when some other had come unto Him, and was asking leave to bury his own father, not even this did He permit him to do: to signify that before all we ought to esteem the following of Himself. But if thou should say, "the promise is very great;" even for this do I most admire them, for that when they had not as yet seen any sign, they believed in so great a reach of promise, and accounted all but second to that attendance. And this, because they believed that by what words they were caught, by the same they would be able to catch others also.