'Used' in the Bible

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.

David answered the priest, “Be assured that women have been kept from us in these three days since I set out, and the bodies of the young men were consecrated (ceremonially clean), although it was an ordinary (unconsecrated) journey; so how much more will their vessels be holy today?”