'Understandest' in the Bible

What knowest thou, that we know not? What understandest thou, which is not in us?

Thou knowest my downsitting and mine uprising; Thou understandest my thought afar off.

Lo, I will bring a nation upon you from far, O house of Israel, saith Jehovah: it is a mighty nation, it is an ancient nation, a nation whose language thou knowest not, neither understandest what they say.