'Cannot' in the Bible

You must not turn away, for then you would go after futile things which cannot profit or rescue, because they are futile.

Then David fastened his sword over his armor and tried to walk, [but he could not,] because he was not used to them. And David said to Saul, “I cannot go with these, because I am not used to them.” So David took them off.

When Saul saw David going out against the Philistine, he said to Abner the captain of the army, “Abner, whose son is this young man?” And Abner answered, “By your life, O king, I do not know.”

Now then, know this and consider what you should do, for evil is [already] planned against our master and against all his household; but he is such a worthless and wicked man that one cannot speak [reasonably] to him.”