The parable of the rye grass is a powerful metaphor:
The kingdom of heaven is like a field in which a man sowed good seed. While men slept, his enemy came and sowed rye grass [a weed that looks like wheat] among the wheat, and went on his way. When the wheat sprung up and brought forth fruit, the rye grass appeared as well.
“Sir, didn’t you sow good seed in your field?” the servants of the householder came and asked. “Why does it have so many weeds?
“An enemy has done this,” he said to them.
“Do you want us to pull them up?” the servants asked.
“No, lest while you pull up the weeds, you also root up the wheat,” he said. “Let both grow together until the harvest. Then I will tell the reapers to first gather the weeds, and bind them in bundles to burn them, and gather the wheat into my barn.”
Jesus explains the meaning to his disciples. I’ve paraphrased his explanation:
The field is the world. The good seeds are those who are on the right path to enter the kingdom of heaven. The rye grass seeds are those who do not have the strength to do so. The enemy who sowed them is the temptation of their desires. Before the kingdom of heaven on earth is revealed, they will be rooted out from among those who are ready. Their family lines will be burned in the fires of their own desires. Then the righteous shall shine forth like the sun in the kingdom of heaven.
One has only to look at the hedonistic values and falling birthrates of the western world to see how the weeds in our society are working toward their own destruction. Ideologies that are in violent opposition to Jesus’s vision of the kingdom of heaven are a much greater threat today than the unrighteous among us. Those who would plant them among us in the fields of the righteous are truly the adversaries of the Son of Man.