(You can read post one here - On the danger of reading Christian literature over the Bible.)
(You can read post two here - On why we need to have private devotions.)
(You can read post three here - On what to do during private devotions.)
(You can read a brief biograpy of George Muller here.)
(September, 1839 [34 years old]) I want to encourage all believers to get into the habit of rising early to meet with God. How much time should be allowed for rest? No rule of universal application can be given because all persons do not require the same amount of sleep. Also the same persons, at different times, according to the strength or weakness of their body, may require more or less. Most doctors agree that healthy men do not require more than between six or seven hours of sleep, and females need no more than seven or eight hours.
Children of God should be careful not to allow themselves too little sleep since few men can do with less than six hours of sleep and still be well in body and mind. As a young man, before I went to the university, I went to bed regularly at ten and rose at four, studied hard, and was in good health. Since I have allowed myself only about seven hours, I have been much better in body and in nerves than when I spent eight or eight and a half hours in bed.
Someone may ask, “But why should I rise early?” To remain too long in bed is a waste of time. Wasting time is unbecoming a saint who is bought by the precious blood of Jesus. His time and all he has is to be used for the Lord. If we sleep more than is necessary for the refreshment of the body, it is wasting the time the Lord has entrusted us to be used for His glory, for our own benefit, and for the benefit of the saints and unbelievers around us.
Just as too much food injures the body, the same is true regarding sleep. Medical persons would readily agree that lying longer in bed than is necessary to strengthen the body actually weakens it.
It also injures the soul. Lying too long in bed not merely keeps us from giving the most precious part of the day to prayer and meditation, but this sloth leads also to many other evils. Anyone who spends one, two, or three hours in prayer and meditation before breakfast will soon discover the beneficial effect early rising has on the outward and inward man.
It may be said, “But how shall I set about rising early?” My advice is: Do not delay. Begin tomorrow. But do not depend on your own strength. You may have begun to rise early in the past but have given it up. If you depend on your own strength in this matter, it will come to nothing. In every good work, we must depend on the Lord. If anyone rises so that he may give the time which he takes from sleep to prayer and meditation, let him be sure that Satan will try to put obstacles in the way.
Trust in the Lord for help. You will honor Him if you expect help from Him in this matter. Pray for help, expect help, and you will have it. In addition to this, go to bed early. If you stay up late, you cannot rise early. Let no pressure of engagements keep you from going habitually early to bed. If you fail in this, you neither can nor should get up early because your body requires rest.
Rise at once when you are awake. Remain not a minute longer in bed or else you are likely to fall asleep again. Do not be discouraged by feeling drowsy and tired from rising early. This will soon wear off. After a few days you will feel stronger and fresher than when you used to lie an hour or two longer than you needed. Always allow yourself the same hours for sleep. Make no change except on account of sickness. (Autobiography, 117-119. Emphasis mine.)