'Understand' in the Bible

He supposed his brethren to be aware that by him God was sending them deliverance; this, however, they did not understand.

So Philip ran up and heard the eunuch reading the Prophet Isaiah. "Do you understand what you are reading?" he asked.

"Understand therefore, brethren, that through this Jesus forgiveness of sins is announced to you;

So Paul associated with the men; and the next day, having purified himself with them, he went into the Temple, giving every one to understand that the days of their purification were finished, and there he remained until the sacrifice for each of them was offered.

"'Go to this people and tell them, you will hear and hear, and by no means understand; and will look and look, and by no means see.