The Foundation -
People often say, "Practice what you preach!" This is usually meant in some sort of negative way, trying to give someone a little of their own medicine. However, in verse 47, it says something very similar. Instead of practicing what WE are preaching, we need to practice what CHRIST was preaching. We need to be men and women of action. He goes on to give an example of how this can be accomplished.
God's Word should be the "foundation" of our lives. Our relationship with Christ is built upon it. To have a strong foundation, we must be constantly studying the scriptures, giving the Holy Spirit opportunities to speak to us. The devil will try to tempt us and distract us, but we will remain strong, because of the strength that Christ provides for us. When Christ is in your life, there is nothing that cannot be done with His help.
However, if we do not focus on God's Word, and instead focus on earthly treasures, we will have a weak foundation. Sure, we may go to church every Sunday, and try to live a Godly life. We may even pray every night before we go to bed. Our lives may be very stressful and busy, not "allowing" you to spend time in God's Word. This is when the devil is most likely to attack. According to the scripture, the attack will not just damage us, but completely destroy us.
This short segment of scripture is very convicting. It reminds us that daily readings and time with God are essential to the strength of our faith. It is not something that should necessarily consume our entire day. It is amazing how important and rewarding a simple 10 minute reading can be to a believer. It can help start the day off right, help bring peace on a lunch break, or give a peace of mind before bed. Whenever you choose to do it, remember to strengthen your foundation!