Charles H. Spurgeon on Psalms 19:13

"The great transgression." Watch very diligently against all sin; but above all, take special heed of those sins that come near to the sin against the Holy Ghost; and these are, hypocrisy, taking only the outward profession of religion, and so dissembling and mocking of God; sinning wilfully against conviction of conscience, and against great light and knowledge, sinning presumptuously, with a high hand. These sins, though none of them are the direct sin against the Holy Ghost, yet they will come very near to it: therefore take special heed of them, lest they, in time, should bring you to the committing of that unpardonable sin. —Robert Russel, 1705.