There are plenty of people who build an entire argument citing only the Kōjien, saying 'This is what the Kōjien says'.
Literal
''Kōjien [locative-に] this-way written is'' [quotative-と] say-[て form], Kōjien [object-を] sole [possessive-の] base [locative-に] argument [object-を] stretch people [subject-が] often exists.
A cultural/rhetorical critique. 広辞苑 (こうじえん) is the authoritative, highly respected Japanese dictionary published by Iwanami Shoten — often the default reference in arguments about word meanings. 拠り所 (よりどころ) means 'foundation, grounding, support' — what one leans on for an argument. 論陣を張る ('to stretch out the ranks of argument') is a literary idiom for 'to set up an argument, mount a debate'. The critique is about people who over-rely on one dictionary as if it settled all meaning disputes.