"Nurses make sure you get the point," said the sign in the injection clinic. In order to get an injection, you have to get the point of the needle. In order to be saved you have to get the point. Not the point of the needle but the point of the cross.
Now I make known to you, brethren, the gospel which I preached to you, which also you received, in which also you stand, by which also you are saved, if you hold fast the word which I preached to you, unless you believed in vain. (1Co 15:1-2)
In vain means "without a point". Like a foggy road on which a driver has no idea where he is going, so is the person who exercises pointless faith. They are participating in a religious exercise but not a life changing process. Instead of having a clear intention as to why they wanted to believe, they believed in a fog. Foggy belief is not acceptable. Christ faced the point of the spears, the points of the crown of thorns, the points of the nails for us. At the very least, our faith should have a point to it too.