Timothy Keller was the son of William B. Keller and Louise A. Clemente Keller. He was born and grew up in Allentown, Pennsylvania, receiving his B.A. from Bucknell University, his M.Div. from Gordon-Conwell Seminary, and both a Doctor of Ministry and a Doctor of Divinity from Westminster Seminary in Philadelphia, Pennsylvania.

Keller was married to Kathy Louise Kristy of Pittsburgh in January 1975. Together they raised three sons: David Andrew (b. 1978), Michael Stephen (b. 1980), and Jonathan Daniel (b. 1983), each born in Hopewell, Virginia.

As a family, the Kellers planted Redeemer Presbyterian Church in New York City in 1989, which grew to a weekly attendance of over 5,000 people, and through which God brought many other fruitful ministries, such as Redeemer City to City, Hope for New York, and Redeemer Counseling Services, among others. After stepping down as Senior Pastor of Redeemer in July of 2017, he continued to serve City to City full-time, a ministry that has helped start more than 1,000 churches in over 150 cities, and trained or reached more than 79,000 leaders.  

He was ordained into the Presbyterian Church in America in 1975 and served as pastor of West Hopewell Presbyterian Church from 1975-1984 and as senior pastor of Redeemer Presbyterian Church in New York City from 1989-2017. From 1984-1989 he taught at Westminster Seminary in the Practical Theology department and served on the staff of Mission to North America as director of Mercy Ministry of the PCA.

Tim authored numerous books, with some of the best known being The Reason for God, The Prodigal God, and The Meaning of Marriage, which he co-authored with Kathy.  Overall, God allowed him to author 31 books that have sold over 6 million copies and have been translated into 29 languages.

Tim is survived by his wife Kathy, his three sons David, Michael and Jonathan, his sister Sharon Johnson of Sorrento, Florida, his daughters-in-law Jennifer, Sara, and Ann-Marie, and seven grandchildren – Lucy, Kate, Charlotte, Miles, William, Eleanor, and Daniel.