The professor in one of my education classes enjoys having people debate, discuss and disagree with one another about how they would handle the educational issues facing public schools today. Because of my faith, some people want to believe that because of our humility we are too weak to defend ourselves. Titus 3:1-3, as I have found, says quite differently: "Remind the people to be subject to rulers and authorities, to be obedient, to be ready to do whatever is good, to slander no one, to be peaceable and considerate, and to show true humility toward all men. At one time we too were foolish, disobedient, deceived and enslaved by all kinds of passions and pleasures. We lived in malice and envy, being hated and hating one another."
I think when Christ asks to humble ourselves, it's for two reasons: as an act of worship that glories God, but more importantly to keep our own pride in check. Note that neither of these reasons mentions weakness. Regardless where we are in our walk with Christ, we all still have struggles and combat against worldly desires. The act of humbling ourselves demonstrates the strength that comes from Jesus. I think even the most faithful of Christians try getting by with their own power alone. More often than not, it's this that leads us into more trouble than we began with - just proving that our own pride - hubris - can become our greatest weakness.
I think it's so amazing that Christ operates counter-intuitively than how the world expects us to. When hardships come upon the faithful, it is those who admit their inability to overcome it that are blessed with the power to remain strong, and even sometimes grow from these experiences. So when the going gets tough, the tough become humble - either by their own will or by God's.
Please, don't mistake humility of weakness. Jesus is so much bigger than that.