The following means, however, ought to be used, according to George Mueller:
1. The careful reading of the word of God, combined with meditation on it.
Through reading of the word of God, and especially through meditation on the word of God, the believer becomes more and more acquainted with the nature and character of God, and thus sees more and more, besides His holiness and justice, what a kind, loving, gracious, merciful, mighty, wise, and faithful Being He is, and, therefore, in poverty, affliction of body, bereavement in his family, difficulty in his service, want of a situation or employment, he will repose upon the ability of God to help him, because he has not only learned from His word that He is of almighty power and infinite wisdom, but he has also seen instance upon instance in the Holy Scriptures in which His almighty power and infinite wisdom have been actually exercised in helping and delivering His people; and he will repose upon the willingness of God to help him, because he has not only learned from the Scriptures what a kind, good, merciful, gracious, and faithful being God is, but because he has also seen in the word of God how, in a great variety of instances He has proved Himself to be so. And the consideration of this, if God has become known to us through prayer and meditation on His own word, will lead us, in general at least, with a measure of confidence to rely upon Him: and thus the reading of the word of God, together with meditation on it, will be one especial means to strengthen our faith.
2. As with reference to the growth of every grace of the Spirit, it is of the utmost importance that we seek to maintain an upright heart and a good conscience,
and, therefore, do not knowingly and habitually indulge in those things which are contrary to the mind of God, so it is also particularly the case with reference to the growth in faith. How can I possibly continue to act faith upon God, concerning anything, if I am habitually grieving Him, and seek to detract from the glory and honour of Him in whom I profess to trust, upon whom I profess to depend? All my confidence towards God, all my leaning upon Him in the hour of trial will be gone, if I have a guilty conscience, and do not seek to put away this guilty conscience, but still continue to do the things which are contrary to the mind of God. And if, in any particular instance, I cannot trust in God, because of the guilty conscience, then my faith is weakened by that instance of distrust; for faith with every fresh trial of it either increases by trusting God, and thus getting help, or it decreases by not trusting Him; and then there is less and less power of looking simply and directly to Him, and a habit of self-dependence is begotten or encouraged. One or the other of these will always be the case in each particular instance. Either we trust in God, and in that case we neither trust in ourselves, nor in our fellow-men, nor in circumstances, nor in anything besides; or we DO trust in one or more of these, and in that case do NOT trust in God.