Hence the solemn earnestness of these warnings. It was not only a doctrine more or less that was at stake, but it was their eternal life. Certain truths believed would increase the firmness of their hold on their Lord, and thereby would secure the prize. Disbelieved, the disbelief would slacken their grasp of Him, and thereby would deprive them of it. We are often told that the gospel gives heaven for right belief, and that that is unjust. But if a man does not believe a thing, he cannot have in his character or feelings the influence which the belief of it would produce. If he does not believe that Christ died for his sins, and that all his hopes are built on that great Saviour, he will not cleave to Him in love and dependence. If he does not so cleave to Him he will not draw from Him the life which would mould his character and stir him to run the race. If he do not run the race he will never win nor wear the crown. That crown is the reward and issue of character and conduct, made possible by the communication of strength and new nature from Jesus, which again is made possible through our faith laying hold of Him as revealed in certain truths, and of these truths as revealing Him. Therefore, intellectual error may loose our hold on Christ, and if we slacken that, we shall forfeit the prize. Mere speculative interest about the less plainly revealed corners of Christian truth may, and often do, act in paralysing the limbs of the Christian athlete. "Ye did run well, what hath hindered you?" has to be asked of many whom a spirit akin to this described in our text has made languid in the race. To us all, knowing in some measure how the whole sum of influences around us work to detach us from our Lord, and so to rob us of the prize which is inseparable from His presence, the solemn exhortation which He speaks from heaven may well come, "Hold fast that thou hast; let no man take thy crown." III. The source and manner of all true growth is next set forth, in order to enforce the warning, and to emphasize the need of holding the Head.