Constantly oppressed by the onslaught of the nations, they would never feel that they did not need the Lord's help.  Hence they would always meditate on him, and they would neither lapse into sluggish inactivity nor lose their ability to fight and their training in virtue.  For frequently security and prosperity have brought low those whom adversities cannot overcome. (Conference 4.6.5, commenting on Judges 3.1-2)

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It is clear from these facts that this struggle of flesh and spirit against one another which rages in us is not only not bad but is even of great benefit to us. (Conference 14)

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If the kingdom of God is within us and that is a kingdom of justice, of peace, and of joy then whoever remains with these virtues is certainly in the kingdom of God. (Romans 14.17)  By contrast, all who deal in unrighteousness, in discord, and in death bearing gloom have taken their stand in the kingdom of the devil, in hell and in lifelessness.  It is by these tokens that the kingdom of God or of the devil is recognized. (Institutes 13)

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It is not possible that the mind should be unapproached by thoughts.  But these must not be attributed completely either to some incursion or those spirits which strive to slip them in among us.  Otherwise man's free will would not remain nor would our task of self-discipline continue to be there...This activity of the heart is compared, not inappropriately, to that of a mill which is activated by the circular motion of water...Only that will be ground which is fed in by the one who is in charge. (Conferences 1.17-18)

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For purity of heart we must practice the reading of the Scripture, together with all the other virtuous activities, and we do so to trap and to hold our hearts free of the harm of every dangerous passion and in order to rise step by step to the high point of love...And so anything which can trouble the purity and the peace of our heart must be avoided as something very dangerous, regardless of how useful and necessary it might actually seem to be. (Conferences 1.7)