甘坚信牧师于1917年8月20日出生在德克萨斯州的麦金尼（McKinney, Texas）。甘牧师从小体弱多病，患有心脏畸形和无法治愈的血液病。他15岁开始卧床不起，医生并不指望他能活多久。1933年4月，在一次戏剧性的重生经历中，他在10分钟内死亡了三次，每次都看到地狱的恐怖，然后又复活了。
1934年8月，甘牧师蒙神的大能、籍由信心于神话语的启示，奇迹般地得了医治，从垂死的病榻上站了起来。在接下来的几年里，耶稣在异象中向甘牧师显现八次，改变了他的事工方向。1967年，他开始了一个定期、并延续到今的无线电广播节目“今日瑞玛”。
甘牧师出版了第一期《信心之道》。该杂志现在每年出版九次，发行量超过20万份。他创办的信心图书出版社已经在全球发行了超过6500万册由甘牧师、肯尼斯·黑根牧师（Kenneth W. Hagin）、琳奈特·黑根牧师（Lynette Hagin）、克雷格·黑根牧师（Craig W. Hagin）和其他人著作的书籍。信心图书出版社也制作了数百万的音频和视频教导媒介。
甘坚信事工的其他外展服事包括：肯尼斯·黑根牧师和琳奈特牧师共同主持的每周电视节目“瑞玛赞美”，瑞玛函授圣经学院，瑞玛校友会，瑞玛国际传道人协会，瑞玛祷告医治中心，以及瑞玛监狱事工。
1974年，甘牧师创办了现在的瑞玛圣经学院。学院在世界各地都有校区，并且还在不断扩大。
直到他回天家前不久，甘牧师继续在全美和加拿大各地旅行布道和教导，主办“全信布道大会”和其他特会。甘牧师被称为“现代信心运动之父”，是一位充满活力的传道人、教师和先知。他的教导和撰书充满了生动活泼的故事，展示了在他和其他人生命中运行的神的大能和真理。人们将记住他不仅是一位伟大的牧师，而且是一位伟大的顾家男人——因为他的家庭也是他的心所在。在每一个里程碑上，他都随时准备与家人交谈、作答，为他们祷告。他每每看到孙子或曾孙都会捧腹大笑。
Rev. Kenneth Erwin Hagin was born on Aug. 20, 1917, in McKinney, Texas. Rev. Hagin was sickly as a child, suffering from a deformed heart and an incurable blood disease. He was not expected to live and became bedfast at age 15. In April 1933 during a dramatic conversion experience, he reported dying three times in 10 minutes, each time seeing the horrors of hell and then returning to life.
In August 1934, Rev. Hagin was miraculously healed, raised off a deathbed by the power of God and the revelation of faith in God’s Word. Jesus appeared to Rev. Hagin eight times over the next several years in visions that changed the course of his ministry. In 1967, he began a regular radio broadcast that continues today as Rhema for Today.
In 1968 Rev. Hagin published the first issues of The Word of Faith. That magazine, now produced nine times a year, has a circulation of over 200,000. The publishing outreach he founded, Faith Library Publications, has circulated worldwide more than 65 million copies of books by Rev. Hagin, Kenneth W. Hagin, Lynette Hagin, Craig W. Hagin, and several other authors. Faith Library Publications also has produced millions of audio and video teachings.
Other outreaches of Kenneth Hagin Ministries include Rhema Praise, a weekly television broadcast hosted by Revs. Kenneth and Lynette Hagin; Rhema Correspondence Bible School; Rhema Alumni Association; Rhema Ministerial Association International; the Rhema Prayer and Healing Center; and the Rhema prison ministry.
In 1974 Rev. Hagin founded what is now Rhema Bible Training College. The school has campuses all over the world and continues to expand.
Until shortly before his death, Rev. Hagin continued to travel and teach throughout the United States and into Canada conducting All Faiths’ Crusades and other special meetings.
Known as the “father of the modern faith movement,” Rev. Hagin was a dynamic preacher, teacher, and prophet. His teachings and books are filled with vivid stories that show God’s power and truth working in his life and the lives of others. He will be remembered not only as a great minister but as a great family man—for his family was his heart. He was there at every milestone ready to talk, to answer, to pray. He was a man whose belly laugh filled the room at the sight of one of his grandchildren or great-grandchildren.