The children have souls, and you have a love for souls, an earnest desire that souls may be saved. Then let the salvation of the soul be your one, constant aim. Let everything tend to this end—everything reach to this.
The means is the gospel of the grace of God. Let this be always prominent, and never let it be lost amid the abundance of your illustration or any desire you may have for teaching.
It may seem foolish to be always harping on one string, but that string has many tones, and remember that, "it is the power of God unto salvation to everyone that believeth." (Rom. 1:1616For I am not ashamed of the gospel of Christ: for it is the power of God unto salvation to every one that believeth; to the Jew first, and also to the Greek. (Romans 1:16)), and we want salvation for the children.
There is the whole Word of God in your hands, and there are an abundance of passages in the Old Testament, as well as in the New, which can be used as illustrating the gospel.