There are two things essential to the growth of animal life. One is food, the other is exercise; and your Christian character will grow by no other means.
Now as to the first. The true means by which we shall grow in Christian grace is by holding continual intercourse and communion with Jesus Christ. It is from Him that all come. He is the Fountain of Life; He gives the life, He nourishes the life, He increases the life. And whilst I have been saying, in an earlier part of this discourse, that we are not to expect an effortless growth, I must here say that we shall very much mistake what Christian progress requires if we suppose that the effort is most profitably directed to the cultivation of specific and single acts of goodness and purity. Our efforts are best when directed to keeping ourselves in union with our Lord. The heart united to Him will certainly be advancing in all things fair and lovely and of good report. Keep yourselves in touch with Christ; and Christ will make you grow. That is to say, occupy heart and mind with Him, let your thoughts go to Him. Do you ever, from morning to night, on a week-day, think about your Master, about His truth, about the principles of His Gospel, about His great love to you? Keep your heart in union with Him, in the midst of the rush and hurry of your daily life. Are your desires turning to Him? Do they go out towards Him and feel after Him? It will take an effort to keep up the union with Him, but without the effort there will be no contact, and without the contact there will be no growth. As soon may you expect a plant, wrenched from the soil and shut out from the sunshine to grow, as expect any Christian progress in the hearts which are disjoined from Jesus Christ. But rooted in that soil, smiled upon by that sun, watered by the perpetual dew from His Heaven, we shall grow like the lily, and cast forth our roots like Lebanon. The secret of real Christian progress and the direction in which the effort of Christian progress can most profitably and effectually be made, is simply in keeping close to our Lord and Master. He is the food of the Spirit. I am come that they might have life, and that they might have it more abundantly.'
Communion with Christ includes prayer. Desire to grow will help our growth. We tend to become what we long to be. Desire which impels to effort will not be in vain if it likewise impels to prayer. We may have the answer to our petition for growth in set ways; we may be "but partially conscious of the answer, nor know that our faces shine when we go among men. But certainly if we pray for what is in such accordance with His will as growth in grace' is, we shall have the petition that we desire. That longing to know Him better and to possess more of His grace, like the tendrils of some climbing plant, will always find the support round which it may twine, and by which it may ascend.
The other condition of growth is exercise. Use the grace which you have, and it increases. Practice the truth which you know, and many things will become clearer. The blacksmith's muscles are strengthened by wielding the forge-hammer, but unused they waste. The child grows by exercise. To him that hath--truly possesses with that possession which only use secures--shall be given.
Communion with Christ, including prayer, and exercise are the means of growth.