In these two chapters on Sunday-school work, we have thus far spoken only of the relation of the school, to the baptized children of Christian parents. A Sunday-school has, however, by no means fulfilled its mission by looking only after those who are already lambs of the flock. A Sunday-school, like a congregation, to be true to itself and its divine Master, must be a missionary institution. In every community there are lambs who have never been in the flock of the Good Shepherd, or have already wandered astray. There are children who have never been either baptized, or instructed in heavenly things at home. Or, if baptized, they have been permitted to grow up afterwards as wild as heathen children. Yes, even in the homes of members of our Church, there are children, whether baptized or not, who are thus growing up utterly neglected. If baptized, they don't even know it. Much less do they know the significance of their baptism. It is the mission of the Sunday-school to gather in these destitute ones, from the street, and from their Christless homes. The Sunday-school must become a spiritual home for them. The earnest teacher can and ought to find out who of his pupils belong to this class, and apply to such the needed instruction and exhortation. In _their_ case it is truly the object of the Sunday-school to lead them to Jesus, to labor for their conversion, to Christianize them. This, as a matter of course, also applies to those, even from Christian homes, who were baptized, and perhaps also, to some extent, instructed in divine things, but who have gone astray, and thus fallen from their baptismal covenant. All such, who are not at present in covenant relationship with Christ, who are turned away from Christ, must be turned back, _i.e._, converted. Now this difficult work, this great change, can be accomplished only through the power of God's Word. "_The law of the Lord is perfect, converting the soul._" "_The Gospel of Christ is the power of God unto salvation._" The words of Christ, "_they are spirit and they are life_." If sinners, whether young or old, are to be reclaimed for Christ, it must be through that Word which "_is quick_"--_i.e._, full of life--"_and powerful and sharper than any two-edged sword_."