'Hard' in the Bible

We all fell to the ground, and I heard a voice speaking to me in the Hebrew language, ‘Saul, Saul, why are you persecuting Me? It is hard for you to kick against the goads.’

For the hearts of these peoplehave grown callous,their ears are hard of hearing,and they have shut their eyes;otherwise they might see with their eyesand hear with their ears,understand with their heart,and be converted,and I would heal them.