Comment: The primary definition of a “weapon” is: “a thing designed or used for inflicting bodily harm or physical damage.”
A "lash" is the flexible part of a whip. A whip is primarily used to cause pain as punishment or as a stimulus to action. I suspect that Jesus wasn't intent on inflicting bodily harm on the moneychangers, and upsetting the tables may have scattered "the merchandise," but there was no physical damage.
Jesus "took the lash" to "stimulate" an examination of conscience: "It is written: 'My house shall be a house of prayer,' but you are making it a den of thieves.'" (Mt. 21:13)
Again, the one time a weapon -- a sword not a whip -- was wielded in Jesus’ presence, he clearly demanded, “Stop, no more of this!” (Lk.21:51)
Jesus "took the lash" once and then laid it down. He said, "I have given you a model to follow." We have taken and continue taking up arms to inflict bodily pain and physical damage. When will we follow Jesus example and lay down all weapons?