'Secretly' in the Bible

Then the king got up in the night and said to his servants, This is my idea of what the Aramaeans have done to us. They have knowledge that we are without food; and so they have gone out of their tents, and are waiting secretly in the open country, saying, When they come out of the town, we will take them living and get into the town.

But Jehosheba, the daughter of King Joram, sister of Ahaziah, secretly took Joash, the son of Ahaziah, with the woman who took care of him, away from among the king's sons who were put to death, and put him in the bedroom; and they kept him safe from Athaliah, so that he was not put to death.

And the children of Israel did secretly against the Lord their God things which were not right, building high places for themselves in all their towns, from the tower of the watchmen to the walled town.