'Able' in the Bible

Now all the Moabites heard that the kings had come up to fight against them. And all who were able to put on armor and older were summoned and stood on the border.

Now therefore, come, make a bargain with my master the king of Assyria, and I will give you two thousand horses, if you are able on your part to set riders on them.

Thus says the king, ‘Do not let Hezekiah deceive you, for he will not be able to deliver you from my hand;