Sowing good seed

The Gospel for this Sunday begins with the parable of the man who sowed good seed in his field. While everyone was asleep his enemy came and sowed weeds all through the wheat, and then went off. When the crop grew and bore fruit, the weeds appeared as well. When the Master was alerted, he said to let the wheat and weeds grow together until harvest. Then the weeds will be burned but the wheat gathered into his barn.
Now, I think we are all trying to sow good seeds and we can see that our crop is growing and bearing fruit; we are also aware of the weeds that spring up, but perhaps this parable calls us to concentrate on the good seed we are sowing and let it grow until God harvests it. We can do nothing without the Holy Spirit and the second reading tells us that "The Spirit comes to the aid of our weakness; for we do not know how to pray as we ought, but the Spirit himself intercedes with inexpressible groanings..." - I think that we cannot see the growth of the good seeds just as we cannot see a blade of grass growing; we need to trust the Spirit so the crop will grow and bear fruit; God will take care of the weeds. Sometimes it is the weeds that keep us humble!