The reapers are the disciples.  The sowers are:

1. Jesus
2. the Samaritan woman
3. John the Baptist
4. the prophets

The harvest is the approaching multitude; but also those whom the disciples have already baptized.  John 3:26, 4:1-2

John 3:26  They came to John and said to him, “Rabbi, that man who was with you on the other side of the Jordan—the one you testified about—well, he is baptising, and everyone is going to him.”

John 4:1-2  The Pharisees heard that Jesus was gaining and baptising more disciples than John,  although in fact it was not Jesus who baptised, but his disciples.

All of history, from Adam to Christ, was a time of sowing. There could be no reaping because Christ had not yet paid for our sins on the cross. The Way to God had not yet been manifested — but it has now! We live in an age of sowing and reaping!

Even though the entire Old Testament was a time of sowing, we are still called to sow today. Jesus spoke of sowing in what we call the parable of the sower (Matt 13:1-23 which is included at the bottom of this page). Besides the obvious applications which Jesus pointed out, there are a couple of other observations that can be made from this parable.

First, the sower did not sow everywhere, just in a limited area. There will always be opportunities for us to sow. We can never sow enough.

Secondly, there is a never-ending supply of seed, much like the miracle of the feeding of the 5000 in (Matt 14:13-21) where the disciples started with 5 loaves and 2 fish and ended with 12 baskets full. We can never run out of seed to sow.

How do we know whether to sow or to reap? Premature reaping results in rotten grain. It never hurts to sow, especially since we can never run out of seed, but to reap before the seed is mature enough to be harvested would be bad for that particular crop. How do we know when the time is right? The answer is that we don’t — but God does. It is vital for sowers and reapers to be in constant communication with the Father, just as Jesus was. When we are sensitive to His leading through His Holy Spirit, then we are truly sent by Him and truly doing His work and the results will be spectacular!

Matthew 13:1-23  That same day Jesus went out of the house and sat by the lake.  Such large crowds gathered round him that he got into a boat and sat in it, while all the people stood on the shore.  Then he told them many things in parables, saying: “A farmer went out to sow his seed.  As he was scattering the seed, some fell along the path, and the birds came and ate it up.  Some fell on rocky places, where it did not have much soil. It sprang up quickly, because the soil was shallow.  But when the sun came up, the plants were scorched, and they withered because they had no root.  Other seed fell among thorns, which grew up and choked the plants.  Still other seed fell on good soil, where it produced a crop—a hundred, sixty or thirty times what was sown.  He who has ears, let him hear.”  The disciples came to him and asked, “Why do you speak to the people in parables?”  He replied, “The knowledge of the secrets of the kingdom of heaven has been given to you, but not to them.  Whoever has will be given more, and he will have an abundance. Whoever does not have, even what he has will be taken from him. This is why I speak to them in parables: “Though seeing, they do not see; though hearing, they do not hear or understand.  In them is fulfilled the prophecy of Isaiah: “‘You will be ever hearing but never understanding; you will be ever seeing but never perceiving.  For this people’s heart has become calloused; they hardly hear with their ears, and they have closed their eyes. Otherwise they might see with their eyes, hear with their ears, understand with their hearts and turn, and I would heal them.’  But blessed are your eyes because they see, and your ears because they hear.  For I tell you the truth, many prophets and righteous men longed to see what you see but did not see it, and to hear what you hear but did not hear it.  “Listen then to what the parable of the sower means:  When anyone hears the message about the kingdom and does not understand it, the evil one comes and snatches away what was sown in his heart. This is the seed sown along the path.  The one who received the seed that fell on rocky places is the man who hears the word and at once receives it with joy.  But since he has no root, he lasts only a short time. When trouble or persecution comes because of the word, he quickly falls away. The one who received the seed that fell among the thorns is the man who hears the word, but the worries of this life and the deceitfulness of wealth choke it, making it unfruitful. But the one who received the seed that fell on good soil is the man who hears the word and understands it. He produces a crop, yielding a hundred, sixty or thirty times what was sown.”