1 John 2:3 We know that we have come to know him if we keep his commands.
How would you answer someone who asks you “How do you know that you believe?” We could be dogmatic and say we “just know” but that is not going to encourage anyone into believing our statement!
One way of answering is highlighted in this verse: if we believe in our Saviour Jesus Christ then we will want to obey His commandments not to justify our belief but because it becomes our way of thinking.
When we believe in our hearts that Jesus Christ died for our sins then others will be able to see that we are serious about our relationship with God because we are living a life for Him instead of against Him like we used to.