Being a Christian based school, the spiritual development of the students was very important to the founding fathers. From inception, church attendance was compulsory. Every Sunday, students were marched to either First Baptist Church or Okediji Baptist Church for Sunday Services.

The idea of having A Chapel started to germinate in the minds of the authorities of this School eighteen months after the establishment of the school (July 22, 1964). On that date a letter was written to the then Executive Secretary of the Baptist Mission of Nigeria, Dr. I. N. Patterson, requesting for funds to be used for the erection of a Chapel. On September 24, 1964 a reply was received from the Baptist Mission to the effect that a grant of 12,000 dollars had been approved by the Mission Board. The school authority was very happy that the Mission understood the great need for a place of worship that would befit the institution.

On June 12, 1968, Dr. Edgar H. Burks, the Executive Secretary of the Baptist Mission of Nigeria, on behalf of the Baptist Mission informed the principal that the Foreign Mission Board had approved a grant of $12,000 (approximately £4,250) for the construction and furnishing of a Chapel at Ilora Baptist Grammar School trusting that the construction of the Chapel would result in the spiritual growth and strength of the school and in the glory of God.

The foundation stone was laid on September 23, 1968 by the Revd. H. D. Martin of the Baptist Mission, Oyo, and was watched by a great number of Christian friends, on that day.

The building and furnishing of the sanctuary were completed at the cost of £3,675 and £580:6s:5d respectively and the church was ready for use by May 29, 1969. The chapel was designed to accommodate about 600 worshippers. The Chapel is today a monument of the Christian love and fellowship of our American benefactors across the sea.

The Baptist Mission of Nigeria constructed replica worship centres (same structural design and capacity) in its schools in Iwo, Shaki, Ire and others. That in Ilora was christened “The Chapel of Trinity” and was commissioned by Rev’d Dr. E. H. Burcks who also gave the keynote address, on Saturday 5th July 1969. The following were the first officers of the chapel;

• Chaplain – Mr. E. A. Adeoye (Senior Tutor)
• Chaplain – Mr. J. O. Olagboye
• Chapel Prefect – Mr. Yomi Ige
• Music Director – Prof. ‘Tunji Augustus

Oyo State Government took over Secondary Schools in the state, including this school, by edict No.14 of September 8, 1975.

In 1985, the Nigerian Baptist Convention in solving the crisis in Olivet Baptist High School decided that all existing Baptist Chapels in all Baptist Colleges be organized into full-fledged churches and clearly demarcated. Consequent upon this, the Chapel of Trinity became Trinity Baptist Church, Ilora on 3rd March 1996 but the physical demarcation was carried out in 2021.