R T Kendall wrote: "I know not a few Christians who have been converted for years, but still question their assurance of eternal salvation. It is not because they don't believe in 'once saved always saved', but because they aren't really sure they have been saved and that it applies to them. Such people don't realise they are in the very grip of Satan. They try to live in a godly manner, but it gets them nowhere regarding joy; neither do they have fellowship with the Father – all because they don't take the simplicity of God's Word to heart."

Although, to my ears, these words sound rather harsh and black and white, I find them very challenging. I do struggle with assurance and have good days and bad days; quite different from my dear wife. So let's look at Kendall's solution: "all because they don't take the simplicity of God's Word to heart". Surprisingly it brings a challenge not only to the insecure but also to the secure.

First of all, what is the simplicity of the gospel? Paul wrote: "If you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved; for with the heart one believes and is justified, and with the mouth one confesses and is saved" (Rom. 10:9-10). Jesus said: "Truly, truly, I say to you, whoever hears my word [takes it to heart; makes room for it in their hearts] and believes him who sent me [believes the Father's testimony about me] has eternal life. He does not come into judgement [he will not be condemned in the final judgement], but has [already] passed from death to life" (John 5:24). Paul also wrote: "By grace you have been saved through faith. And this is not your own doing; it is the gift of God, not a result of works, so that no one may boast" (Eph. 2:8-9). And John wrote: "To all who received him [Jesus], who believed in his name, he gave the right to become children of God" (John 1:12). Only three things are required of us: to believe in Jesus; to receive him as Lord and Saviour and to confess out loud that he is God.

Secondly, what does it mean to take the simplicity of the gospel to heart? I have not properly thought about this before. Dictionary definitions of the actual saying "take to heart" seem to major on the negative: "to take criticism overly seriously and be deeply affected and upset by it", "to constantly analyse and think painstakingly and frequently about something negative that affects you personally". In such cases we need to forgive the people involved and renounce all resentment. "Watch out that no poisonous root of bitterness grows up to trouble you, corrupting many" (Heb 12:15).

If I struggle with assurance, what have I taken to heart? It cannot be the promises of God. It must be the constant lies and accusations of the evil one. To take the devil's words to heart is to honour him and not to take God's promises to heart is to dishonour our Creator, our Father and our Saviour. How do we get this truth from our heads to our hearts? By listening to, and taking to heart, all the positive things fellow believers say to us about ourselves. By stopping, accepting, meditating on and asking God to confirm to us what they have been saying. When I do this, I get the Father's affirmation and my assurance grows.