'Knowledge' in the Bible

And the churches of Judaea which were in Christ still had no knowledge of my face or person:

But at that time, having no knowledge of God, you were servants to those who by right are no gods:

But now that you have come to have knowledge of God, or more truly, God has knowledge of you, how is it that you go back again to the poor and feeble first things, desiring to be servants to them again?

But you have knowledge that with a feeble body I was preaching the good news to you the first time;