'Once' in the Bible

The king used to go to Gibeon to sacrifice, since there was a famous high place there, where Solomon once offered 1,000 burnt offerings on that altar.

because the king had ships that sailed to Tarshish accompanied by Hiram's ships. Once every three years ships from Tarshish returned, bringing gold, silver, ivory, apes, and peacocks.

So once he heard that Naboth was dead, Ahab got up, went down to the vineyard of Naboth the Jezreelite, and confiscated it.