One of the main causes of lukewarm pastorates and churches is the attempt progress in sanctification by self-effort.
Although it is obvious that the epistle to the Galatians refutes the heresy that the works of the Mosaic law are necessary to become a child of God (Gal 1:6-9; 3:23-29), it is not as apparent that it also teaches sanctification by grace through faith, enabled by the Holy Spirit (Gal. 2:20,21;3:1-3; 5:56,22,23). This latter aspect of the gospel is vital and liberating.
This discovery led to the development of The Sonship Course by Dr. Jack Miller of Serge Ministries.
But preaching Galatians verse by verse can come across as culturally remote and merely academic. For a sermon series that unpacks the message of Galatians with an exemplary blend of exposition, illustration and application, see the “Be Free” series preached by the pastors at Bayside Chapel in Barnegat, New Jersey. www.Baysidechapel.org