Today's parable speaks about the Kingdom of God and consoles us when we see the evil that afflicts our world and frequently blemishes our Church. We may also apply the doctrine of the parable to our spiritual lives.
The parable contains both "warnings" and "consolation". The first warning is that there is an enemy, who goes about sowing weeds among the wheat. These weeds represent all the evils which come from the enemy, the devil, both the major evils which afflict humanity and the probably more minor evils which afflict all of us personally, whether physical, psychological or spiritual. God does not necessarily heal us here and now, but we do have the consolation of experiencing God's patience in dealing with us.
We can be consoled by the doctrine that nothing happens without God's knowledge: "I see an enemy's hand in this." If God looks at us and finds that we have sinned, no doubt he sees the hand of our enemy, the devil.
We are also consoled by the fact that the weeds do not completely destroy the wheat crop: in judging us, God sees quite clearly our goodness as well as our weaknesses which sometimes degenerate into sin.
Father in Heaven, as You are patient with us, teach us to be patient with ourselves and others, for we are weak and often fail.