'Hard' in the Bible

Likewise all the men of Israel who had hidden themselves in the hill country of Ephraim, when they heard that the Philistines fled, even they also followed hard after them in the battle.

The Philistines followed hard on Saul and on his sons; and the Philistines killed Jonathan, and Abinadab, and Malchishua, the sons of Saul.

The battle went hard against Saul, and the archers overtook him; and he was greatly distressed by reason of the archers.