|Romanesque compound arches:
Framing the tympanum are the rolled moldings for which Lombard architecture was so famous. On the molding nearest to the Blessed Trinity relief are the Signs of the Zodiac, e.g., Crab/Cancer, Scales/Libra. In Christian symbolism the twelve months are the twelve Apostles .
These ancient symbols were sometimes used in medieval architecture over doorways to remind the individual entering a church of the value of time and its never-returning passage.
The Trinity -- Father, the Son, and Holy Spirit (dove above the Father) -- is surrounded by angels, quite appropriate, given the name of the church.
The large terra cotta piece was sculptured by P. Kuhnle. His name appears on all the interior ceramic (terra cotta) reliefs over the doorways. Little is known about him besides the fact that he worked for the O W. Ketchem Company (with headquarters at Philadelphia) and worked out of their Crum Lynne terra cotta factory (This was located five miles northeast of Chester and has long since closed.)
Caption source: "Guidebook to Blessed Trinity R.C. Church," by Rev. Walter Kern, 1976