Summary: Why does evil exist in the world and what are we to do about it? Jesus tells a good story and has some sober advice as we look at ourselves - are we weeds or wheat?
Today we are going to talk about three parables that give us an idea of the effect of the gospel in the world. Last time we looked at the parable of the sower, which describes how the individual is or is not open to the gospel. Now we turn outward to look at how the gospel spreads. First century Jews would have been familiar with the concept of the kingdom of God. Daniel especially spoke about an everlasting kingdom. God’s promise to David was that there would be someone always on his throne.
They looked for a political kingdom, Jesus came to explain that His kingdom would start in ways they did not expect and would be a spiritual kingdom before it was a physical kingdom on this earth, which means it exists invisibly, for now.
24 – 30
Darnel (Tares or False wheat) grows in Syria and Israel to a meter in height. It is poisonous and is black when ripe, whereas wheat turns brown. It is very similar to wheat until the heavy heads on the real wheat weigh down the plant—this doesn’t happen with darnel. To purposefully plant darnel in a field was punishable under Roman law.
“An enemy did this.” Evil comes from Satan, not God.
The presence of weeds does not stop the growth of the wheat.
31 – 32
Like a diamond, which you need to turn it around in the light to see all its facets, so too the effect of the gospel must be seen from various pictures. This one tells us that although the kingdom of God starts small, with just Jesus Himself, it will grow into a significant thing, just as a mustard seed starts out as one of the smallest, but grows into a tree 10-12 feet tall in just weeks.
Normally a kingdom would come into new territory by a massive overwhelming force, but Jesus came alone—His kingdom, as we’ll see next, grows on the inside but is very powerful and all encompassing. Today there are over 1 billion Christians in the world (www.Christianity.com).
If you add a small amount of yeast to bread dough it will consume sugar and release carbon dioxide throughout the dough. In the same way, adding a small amount of the gospel spreads invisibly but thoroughly throughout the world. Yeast itself doesn’t add color or taste but does give texture and lightness to what otherwise would be a hard crusty loaf. Even though you can’t see that someone is a Christian or not, the character of light that the Holy Spirit gives to each one of us permeates our character and spreads out to others.
34 – 35
Jesus is quoting from Psalms 78:2-4 (quickview)  I will open my mouth in a parable; I will utter dark sayings from of old, 3 things that we have heard and known, that our fathers have told us. 4 We will not hide them from their children, but tell to the coming generation the glorious deeds of the Lord, and his might, and the wonders that he has done.
This Psalm was used to remind Israel of all that God had done for them – and the way many rebelled against God. A parable is a story with a spiritual point, and Jesus’ point was to remind people of things they should have known, but were now blind and deaf to based on their own rebellion.