Ask, and it will be given to you...knock, and the door will be opened to you...for your heavenly Father knows how to give good things to those who ask him. Our Gospel passage for today is a continuation of the section to which we were introduced on Tuesday (part of a larger section covering the fifth through the seventh chapters). After teaching his disciples how to pray (6:9-13), Jesus went ahead to give a deeper meaning of the Lord's Prayer. The Lord’s Prayer is itself an exhortation calling us to be aware of God's presence to us at all times so that when a need arises, we do not hesitate to approach God with our petitions. When we get to know and experience God as one who is so close to us, it becomes easy for us to confidently "bother God with our needs." As a continued explanation of the Lord’s Prayer, today's reading seems to be linked to the fourth petition:  Give us today our daily bread.
The most human of all the petitions,  Give us our daily bread is a petition that is not limited to bread (bodily nourishment) alone. It is a petition that covers in entirety all our basic human needs (food, shelter, clothing). In other words, it is a petition that asks God to grant us what is necessary for existence. By telling us that when we ask it will be given us and that when we knock the door will be opened for us, Jesus is simply encouraging us to turn the desires of our hearts to the Lord. He knows that because of our pride, we are always tempted not to turn our cares over to God and instead try to provide for ourselves. And we know the result of such an endeavor, for it is what Adam and Eve did. They thought they could give themselves life by their own power, that they did not need God anymore. What followed was violence and destruction of the earth. Brothers turned against each other and fought for survival. This is what happens when we try to provide for ourselves by our own power. Need quickly turns into greed, and providing for "today" turns into amassing for tomorrow (Pope Benedict XIV,  Jesus of Nazareth). 
Asking God to for our daily bread frees us to pursue our orientation to self-transcendence. Freed from greed and the violence that accompanies it, we become free to love, free to be sisters and brothers to one another and to be sons and daughters of God. This is the freedom that must characterize the kingdom of God ushered in by Jesus.