The age of service fixed for the men of the tribes may yield suggestions for our time. It is not of warlike service we have to think, but of that which depends on spiritual influence and intellectual power. And we may ask whether the limits on one side and the other have any parallel for us. Young men and women, having reached the age of bodily and mental vigour, are to hold themselves enrolled in the ranks of the army of God. There is a time of learning and preparation, when knowledge is to be acquired, when the principles of life are to be grasped, and the soul is to find its inspiration through personal faith. Then there should come that self-consecration by which response is made to the claim of God. Neither should that be premature, nor should it be deferred. When an aimless, irresolute adolescence is followed by years of drifting and experimenting without clear religious purpose, the best opportunity of life is thrown away. And this far too frequently occurs among those on whom parental influence and the finest Christian teaching have been expended. The time arrives when such young men and women should begin to serve the Church and the world; but they are still unprepared because they have not considered the great questions of duty, and seen that they have a part to play on the field of endeavour. It is true, no time can be fixed. The public service of Christ has been begun by some in very early youth; and the results have justified their adventure. From the humble tasks they first undertook they have gone on steadily to places of high responsibility, never once looking back, learning while they taught, gaining faith while they imparted it to others. Each for himself or herself, in this matter of supreme importance, must seek the guidance and realise the vocation of God. But delay is often indulged, and the twentieth, even the thirtieth year, passes without a single effort in the holy service. One could wish for a Divine conscription, a command laid on every one in youth to be ready at a certain day and hour to take the sword of the Spirit.