It is not enough when men have discovered an evil heart of unbelief, and turned again in repentance, that they take up the thread of life which has become ravelled. Perverse faithlessness cannot be cured by a sudden decision to resume the duty which was abandoned in fear. The refusal was no superficial thing, but had its source in the springs of will, the character and habits of life. We are apt to judge otherwise, and to suppose that we can alter the whole current of our nature by a single act of choice. To-day the trend is strongly in one direction, along a channel which has been forming for many years; to-morrow we think it possible to become other men, strong where we were weak, determined upon that which we abhorred. But something must intervene; some change must take place deeper than our impulse. We must have the new heart and the right spirit; and in proportion to the gravity of the situation and the importance of the duty to be done must the time of discipline be long. The wilderness wandering had to be for many years because the temper of a whole people was to be altered. For a single person a far shorter ordeal may suffice. He may pass through the stages of conviction, repentance, and new creation in a few weeks or even days. Nay, sometimes the regenerating Spirit brings about the change apparently in a moment. Yet the rule is that stability in faith must come slowly, that the way of trial cannot be hastened. A great task, therefore, the right doing of which is necessary to the open vindication of religion, may not be gone about in a sudden change of mind. We are not to take lightly, into untried hands, the massive plough of the kingdom of God. In Canaan, the Amalekites and Canaanites, Moses said, would dispute the advance of Israel,--Amalekites skilled in desultory war, Canaanites long trained in military art. These would fight without any sense of the support of the true God. But how would the Hebrews speed, meeting them on the same footing? The contest would be then between human skill and daring on either side; and there could be no doubt as to the issue. Bands of men acquainted with the country, disciplined in war as the tribes of Israel were not, fighting for their fields and homes with a defence of walled cities to fall back upon, would certainly win. If the Hebrews went up, it would be without the sign of Jehovah's presence; the ark of the covenant could not be borne with the army on such an expedition. Their attempt, being presumptuous, must end in disaster.