John 13:2 GNT
Jesus and his disciples were at supper. The Devil had already put into the heart of Judas, the son of Simon Iscariot, the thought of betraying Jesus.
Sometimes I suddenly find myself lost in thoughts that are obviously not glorifying to God in anyway. As soon as I become conscious of what I am thinking however, I immediately fight to get my mind off such thoughts.
Apparently, the devil can sometimes sneak thoughts into our minds just as he did with Judas. Typically, this happens because we have left a window open through which he sneaks in.
Our eyes and ears are typically the windows through which the devil sneaks his thoughts into our heart. Just like a terrorist cell sneaks in small quantities of explosives into a city per time; the devil sneaks in bad information/ideas and hides them in a dank corner until he has stockpiled enough to launch a massive attack on our heart and mind.
The only reason we fall to temptation is because we carelessly allowed the devil to pile up evil thoughts in our hearts until they became too strong for us to resist.
This is why scripture says…
Proverbs 4:23 AMP
Keep and guard your heart with all vigilance and above all that you guard, for out of it flow the springs of life.
Clearly, the Bible takes a militant approach to getting this done: Station a vigilant guard and treat your heart like a high security zone.
In other words, it is far better to keep the devil’s evil thoughts out of our hearts than to try to get them out after they have gone in there. Just the same way that we set ‘call blocking’ on our phones to keep out Robo-calls, and set filters to keep out Spam from our mail boxes, it is wise to set filters to keep the wrong things from getting into our hearts.
We find a very effective filter app in the letter Apostle Paul sent to the Philipian church.
Philippians 4:8 AMP
For the rest, brethren, whatever is true, whatever is worthy of reverence and is honorable and seemly, whatever is just, whatever is pure, whatever is lovely and lovable, whatever is kind and winsome and gracious, if there is any virtue and excellence, if there is anything worthy of praise, think on and weigh and take account of these things [fix your minds on them].