Our Scripture reading today is Proverbs 23:7, "For as he thinketh in his heart, so is he: Eat and drink, saith he to thee; but his heart is not with thee."
It is vital that we guard what we allow into our heart.  What ends up in our heart will greatly affect how we think and act.  What are we wathing on TV?  What books are we reading?  What kind of music do we listen to?  What websites do we find ourselves surfing?  There are numerous ways into our heart.  Satan will do everything he can to use our heart against us.  Jeremiah 17:9, "The heart is deceitful above all things, and desperately wicked: who can know it?"
As children of God, we have the tools necessary to not only guard our heart but also to equip our heart.  God's Spirit with God's Word will help us to daily withstand the wiles of the devil and have victory in our lives.  Colossians 3:16, "Let the word of Christ dwell in you richly in all wisdom; teaching and admonishing one another in psalms and hymns and spiritual songs, singing with grace in your hearts to the Lord."  Joshua 1:8, "This book of the law shall not depart out of thy mouth; but thou shalt meditate therein day and night, that thou mayest observe to do according to all that is written therein: for then thou shalt make thy way prosperous, and then thou shalt have good success."