In response to his calling, Bob devoted himself to theological training to equip himself for the ministry. He obtained a diploma in theology (University of London), a bachelor of theology (Far Eastern Bible College, Singapore), and pursued his master of divinity and master of theology from Covenant Theological Seminary, USA. He further pursued training in a bachelor of arts (honours) in philosophy at London University before going on to complete a doctor of ministry at Temple Baptist Seminary, USA, and a doctor of philosophy at Omega Graduate School (formerly known as Oxford Graduate School), Dayton, USA.

Over the last 43 years, Bob has matured in his ministry as a pastor, teacher and a serial church planter. His ministry extends beyond Singapore to Malaysia, Thailand, Indonesia, Ivory Coast and Kenya. In Singapore, he has fund-raised and developed Sembawang Bible-Presbyterian Church, and planted, fund-raised and developed Moriah Bible-Presbyterian Church and Herald Bible-Presbyterian Church.  In his missionary outreach, he ministers, preaches and teaches in churches and seminars in Malaysia, Thailand and Indonesia.

Despite his heavy pastoral and missionary engagements, Bob continues to commit himself to the training and education of Christian leaders, pastors and missionaries. He lectures at the Evangel Reformed Seminary in Kuala Lumpur and directs the masters programme at Ebenezer International Institute of Biblical Studies of Kenya. In Singapore, Bob helps in curriculum development and teaches at the Asian Pastoral Institute.