The word "is" and "of the word" are understood from the previous phrase. The noun "doer" can also be expressed with the verbs "do" or "obey." AT: "but is not a doer of the word" or "but does not obey the word" (See: [[rc://en/ta/man/translate/figs-ellipsis]])
It is implied that though he may see that he needs to do something, such as wash his face or fix his hair, he walks away and forgets to do it. This what a person who does not obey God's word is like. AT: "then goes away and immediately forgets to do what he saw he needed to do" (See: [[rc://en/ta/man/translate/figs-explicit]] and [[rc://en/ta/man/translate/figs-simile]])
# the person who looks carefully into the perfect law
This expression continues the image of the law as a mirror. (See: [[rc://en/ta/man/translate/figs-simile]])