A retired monk?
Nope--it's a decidedly non-theological surveying instrument for measuring angles in horizontal and vertical planes, although some (and we think maybe these, given the OD paint) are used by the military in meteorology and rocketry. Measures approx 7-1/2" x 5" x 4" with a plethora of moving parts: optical head that pivots up and down; focal knob calibrated from 0 to -90 and +10 to + 80; horizontal and vertical adjustments with a locking lever; and a 1-5/8" dia ball with a 1/2" hole in the bottom for a mount. Weighs in at over 5 lbs. The paint is chipping, but you would too at this age.