'Unable' in the Bible

When they were unable to make payment, he made the two of them free of their debts. Which of them, now, will have the greater love for him?

And why are you, in your hearts, unable to be judges of what is right?

And they all gave reasons why they were not able to come. The first said to him, I have got a new field, and it is necessary for me to go and see it: I am full of regret that I am unable to come.

And another said, I have got some cattle, and I am going to make a test of them: I am full of regret that I am unable to come.