I dont know the gospel is true because my mind could finally make sense of it. I know the gospel is true because of the personal and powerful witness that filled my heart.
I know the gospel of Jesus Christ has the power to soften the hardest of hearts, turn anger into love, provide peace in turbulent times and bless those who werent looking to be blessed. I dont know those truths because someone told me about them, I know them because they happened to me.
And if all that isnt true, nothing is.
The truth is that all of the above is in the bible. Too bad you managed to miss it.