'Sluggish' in the Bible

Speak and say, ‘Thus says the Lord God,“Behold, I am against you, Pharaoh king of Egypt,The great monster that lies in the midst of his rivers,[Boastfully] declaring, ‘My Nile is my own, and I have made it for myself.’

Then Jesus said to them, “O foolish men, and slow of heart to trust and believe in everything that the prophets have spoken!

Concerning this we have much to say, and it is hard to explain, since you have become dull and sluggish in [your spiritual] hearing and disinclined to listen.