After entering active service in the Methodist ministry in 1946, de Silva pursued his tertiary education, obtaining qualifications including a Bachelor of Divinity degree, two Master's degrees, and a Doctor of Theology degree.
Setelah masuk pelayanan aktif dalam pelayanan Methodis pada 1946, de Silva melanjutkan pendidikannya, meraih kualifikasi yang meliputi sebuah gelar Bachelor of Divinity, dua gelar Master, dan sebuah gelar Doctor of Theology.