The word translated here, quite correctly, 'transgression,' and intensified by that strong adjective attached, 'a _great_ transgression,' literally means _rebellion_, _revolt_, or some such idea; and expresses, as the ultimate issue of conscious transgression prolonged and perpetuated into habit, an entire casting off of allegiance to God. 'No man can serve two masters.' 'His servants ye are whom ye obey,' whomsoever ye may call your master. The Psalmist feels that the end of indulged evil is going over altogether to the other camp. I suppose all of us have known instances of that sort. Men in my position, with a long life of ministry behind them, can naturally remember many such instances. And this is the outline history of the suicide of a Christian. First secret sin, unsuspected, because the conscience is torpid; then open sin, known to be such, but done nevertheless; then dominant sin, with an enfeebled will and power of resistance; then the abandonment of all pretence or profession of religion. The ladder goes down into the pit, but not to the bottom of the pit. And the man that is going down it has a descending impulse after he has reached the bottom step and he falls--Where? The first step down is tampering with conscience. It is neither safe nor wise to do anything, howsoever small, against that voice. All the rest will come afterward, unless God restrains--'first the blade, then the ear, then the full corn in the ear,' and then the bitter harvest of the poisonous grain. II. So, secondly, note the help sought. The Psalmist is like a man standing on the edge of some precipice, and peeping over the brink to the profound beneath, and feeling his head beginning to swim. He clutches at the strong, steady hand of his guide, knowing that unless he is restrained, over he will go. 'Keep Thou back Thy servant from presumptuous sins.' So, then, the first lesson we have to take is, to cherish a lowly consciousness of our own tendency to light-headedness and giddiness. 'Blessed is the man that feareth always.' That fear has nothing cowardly about it. It will not abate in the least the buoyancy and bravery of our work. It will not tend to make us shirk duty because there is temptation in it, but it will make us go into all circumstances realising that without that divine help we cannot stand, and that with it we cannot fall. 'Hold Thou me up, and I shall be safe.' The same Peter that said, 'Though all should forsake Thee, yet will not I,' was wiser and braver when he said, in later days, being taught by former presumption, 'Pass the time of your sojourning here in fear.'