If Shang Qi had been a Christian, following Holy See convention, he would certainly have been granted a bishop-level position along with a sacred artifact, assigned to guard a regional church and entrusted with a major responsibility.
However, as a pagan—even though the modern Holy See no longer hunted down non-believers with the merciless zeal of the past—Shang Qi could naturally not be trusted to the same extent as a devout follower.
Yet, a promise of a reward could not simply be broken. Coincidentally, a thorny "dilemma" currently plagued the Holy See, which they could conveniently pass off to Shang Qi.
Chapter 248