'Fortify' in the Bible

And he sent messengers unto Abimelech privily, saying, Behold, Gaal the son of Ebed and his brethren be come to Shechem; and, behold, they fortify the city against thee.

On the fourth day, they got up early that morning, and the descendant of Levi got ready to leave. Then the young woman's father-in-law told him, "Fortify yourself by eating some food before you go."

On the fifth day, he got up early in the morning, but the young woman's father-in-law told him, "Please, fortify yourself," so they delayed until later that afternoon while both of them ate together.