Saint Sava Serbian Orthodox Church was designed to conform to the spirit of Orthodox teaching. According to Orthodox belief, God is eternal King. Hence the church building, which is the sacred home for the worship of God, should be royal in every aspect.

Orthodox Christians have always built their churches with that in mind and have always put into the church everything that they regarded as the best; the sturdiest building materials, the most beautiful adornments and the most costly utensils and vestments they could afford.

If they were not wealthy enough to use pure gold, silver, and precious stones, they used imitations. Earthly royal splendor has always served as a pattern for the expression of heavenly glory.

Orthodox church buildings are designed with the intention to make God, the Heavenly Kingdom and Salvation seem sensibly real and present.

Orthodox churches have strict guidelines they must follow when building a church. The structure of church buildings is usually in the design of a ship or a cross. The ship plan resembles and signifies the ark of Noah in which he and his family were saved from the flood, while the cross plan reminds Christians of the Cross upon which Jesus Christ was crucified.

Strict Orthodox Church guidelines detail that the length of the building must run parallel to the east-west line, so that the church sanctuary is always facing east.

Saint John Damascus (d.753) affirms that it is an Apostolic Tradition to worship facing east. The main entrance of the church is always through the western portal. Most churches have two side doors, the northern and the southern, and Saint Sava Church was built in accordance to all these traditions.

Byzantine architecture evolved from the Roman in the 6th century. The most popular Byzantine plan is a cross pattern in a square. The building is topped by a cupola, a cylindrical or polygonal drum covered with a dome, with narrow arched windows cut all around the concave space.

Oftentimes in Byzantine architecture, the central dome is surrounded by several smaller cupolas on a lower level. Crosses embellish the top of every dome and belfry, signifying the church is glorification of the Crucified Lord and Saviour Jesus Christ.

A great number of Serbian churches and monasteries have been built in the Byzantine style. Originality is expressed both in the design and the ornamentation, and no two churches are alike. Every church can be unique within traditional guidelines. Saint Sava Merrillville was patterned after the church in Topola, Serbia, but differs with its columns and its west-facing windows.

All church buildings must be consecrated by a bishop before a Divine Liturgy can be celebrated. When a church is consecrated or christened, Kumovi (sponsors) are chosen. Glisho Rapaich, Michael and Yvonne Galich served as Kumovi to Saint Sava Church.

Every Orthodox Church is dedicated to a Holy Event in the life of Jesus Christ; to the Most Pure Mother of God; to the Holy Trinity; to the Archangels Michael or Gabriel; to the Holy Apostles or to a Saint or Martyr for Jesus Christ.