There can be no “best” hymn sung by Christian churches, but there are some that are far more popular than others. A few have become classics, sung by generations. Consider John B. Dykes and Reginald Heber’s “Holy, Holy, Holy,” or “Amazing Grace” by E. O. Excell and John Newton.
The former places third on GodTube’s all-time hymn hits list, the latter comes in at No. 1. (GodTube is a Christian-emphasis parallel of the better-known YouTube.)