When there is a disparity in biblical doctrine (e.g. dietary restrictions or social customs) how do religious authorities decide which to uphold when both beliefs are sourced in the Bible?

My own impression is that the Bible exists in Aramaic, Hebrew and Greek. In English, it says what a translator earnestly believes it says.

Moreover, when a person reads the Bible, he/she earnestly believes he/she understands what it says, correctly in every nuance and detail.

In other words, disagreements are part of the fallen world we live in. God reveals Himself in many ways and at many times, and his foremost single ambassador, the Apostle Paul, warns the members of the early church in his letters that Christ crucified, dead, and resurrected – so that we may have his Grace and enter eternal life by being washed in his blood – that much is key. But the farther one gets from that center, i.e. exploring diet or who’s on first etc., the greatest command is to love and accept one another, build each other up in charity, and let the less-consequential details fall to the side.

So, when a believer “owns” some specific set of beliefs regarding diet or social custom, that believer and any other believer in the nearby vicinity are required to pat each other on the head, embrace, hug, and agree that Christ’s death is the only key to salvation.