Gen. {1:29} And God said, Behold, I have given you every herb bearing seed, which [is] upon the face of all the earth, and every tree, in the which [is] the fruit of a tree yielding seed; to you it shall be for meat.

Marijuana can be lawfully eaten.  Herbs in general are natures medicines.

It is lawful according to scripture to eat Marijuana and not to smoke it, but this does not mean that you should eat it for the purpose of intoxication.  It should most properly be used for medicinal purposes obviously but also as meat for prescribe holy days.