In James 1:21 it says,

“So get rid of all the filth and evil in your lives, and humbly accept the word God has planted in your hearts, for is has the power to save your souls.”

The word “planted” in the KJV is “engrafted”.  To engraft is to incorporate in a firm or permanent way; implant.  

James 1:22 says,

“But don’t just listen to God’s word.  You must do what it says. Otherwise, you are only fooling yourselves.”

James 2:14 says,

“What good is it, dear brothers and sisters, if you say you have faith but don’t show it by your actions?  Can that kind of faith save anyone?”

The engrafted word has the power to save your soul because to engraft is to become conformed.  You make two things into one thing. The word of God creates divine inspiration that creates new desires, that create new actions, that create new results.  Therefore the engrafted word saves your souls because it creates real life transformation.  

Let’s say we have an apple tree that produces granny smith apples and we want to graft in a different variety of apples into that tree.  The way we know that the graft was successful is that where the two branches were joined together, new growth has occurred whereby the two branches become one branch.  And then that branch produces fruit.  

You know the word is engrafted when it literally becomes who you are.  Jesus said in John 15, “If any man remain in me and I in him he will bear much fruit.”  Fruit is the outward expression of the inner belief and life source. Which is why you can judge a tree by its fruit.  

James said if you only hear the word but don’t use it, you are fooling yourself.  Knowing what the words are, is not the same thing as know why the words are. How could they save your soul if you don’t know what they mean?  But the engrafted word can save your soul, because when you know why something exists you can use it on purpose and gain all the benefits.