Though many cultures and religions have practiced fasting, it is only that form practiced in the Bible and by God’s people that should interest the Christian. As such, here is what the Bible teaches us about this important discipline:
1. Fasting in the bible (generally) refers to abstinence from all or most of a person’s necessary daily calories for an extended period of time. People fasted for different reasons:
1.1. To mourn the death of loved ones (1Ch 10:12; 1Sa 31:13; 2Sa 3:33-35).
1.2. To demonstrate repentance and seek God’s forgiveness (Lev 16:29-31; Num 29:7 w/Act 27:9; 1Sa 7:1-6; 1Ki 21:27; Neh 1:4-6, 9:1-3; Est 9:30-31; Jon 3:3-9; Psa 69:5-10; Joe 1:14-2:12).
1.3. To seek God’s deliverance, healing, special intervention (2Sa 12:15-16; 2Ch 20:2-3; Ezr 8:21-23; Est 4:3, 16; Psa 35:13; Mat 17:21 w/Mar 9:29; Act 27:18-21, 33-34).
1.4. To seek special revelation, counsel from God (Jug 20:26; Act 13:1-3).
1.5. As the means to special appointment or ministry (1Ki 21:9-12; Act 13:1-3, 14:23; Exo 34:28; Mat 4:1-11; 1Ki 19:8; Dan 10:2-6).
1.6. As the means to exercising/practicing our righteousness or self-control unto God (Mat 6:1 w/16-17 = Notice: 1) the context is practicing righteousness, 2) Jesus prohibits disfiguring your face in sadness, being dirty, disheveled or looking distressed which means that He cannot be referring to the other types of fasting associated w/repentance or mourning since such things were the hallmark of those kinds of fasts – i.e. “sackcloth and ashes”; e.g. Est 4:1-3; Luk 2:36-37; Act 10:30 [BYZ] w/Phi 3:19 w/1Co 9:25-27; Act 24:25; *Mat 4:1-4 = Man lives by self-control/obedience unto God).
2. Jesus makes it clear that fasting is not a matter of “if” but “when” for the Christian (Mat 6:16, 9:14-15 = Notice, Jesus does not contest the need for His disciples to fast, but rather argues that His presence among them marks a special occasion- i.e. a wedding celebration. Notice also, this kind of fast is associated w/mourning, which means that Jesus is condoning those fasts associated w/loss or repentance as well – see Jam 4:8-9 = “be wretched” most likely infers fasting since this as discussed, was how the Jews afflicted themselves when repenting – e.g. Num 29:7; Mat 9:14-15 [btw] is an important text in support of MCT.)
3. Unless a special day or holiday, circumstance or sickness (e.g. day = Mat 9:14-15; circumstances = Joh 21:3-13), devout Jews/Jewish proselytes “snacked” and “fasted” every day until the main meal in the evening (e.g. snack – Rut 2:14) . Hence why when the time of a meal is mentioned in Scripture, the overwhelming evidence points to it as predominately (if not always) taking place only in the evening. Due to lack of sufficient lighting in most homes, this began at 3 p.m. (i.e. sunset) and ended by sundown. In ancient times, this was considered the evening or end of day (e.g. Act 10:30 [BYZ]; Gen 18:1-8; Exo 12:1-18; Mat 14:14-16; 26:17-20; Luk 24:28-30).
4. This does not (however) mean the Jews starved or suffered from mal-nutrition. Though only eating OMAD, those meals were large and contained the remainder of their necessary nutrients. In other words, they fasted for 24 hours yet at the same time, still consumed the full amount of calories needed per day.
5. That this represents the kind of fasting (for the purpose of self-control/practicing righteousness) Jesus expects of us is highly likely given the fact that rarely was fasting ever done for longer periods of time (even in cases of mourning/repentance/guidance/deliverance). The normal fasting period concluded at the evening meal (e.g. guidance = Jug 20:26; repenting/deliverance = 1Sa 7:1-8; mourning = 2Sa 1:8-12, 3:33-35; deliverance = Ezr 9:1-5).
6. As further support for OMAD as the kind of regular fasting practiced in the Bible, one simply needs to consider that the Bible views gluttony not so much in terms of over-eating but eating too often. Multiple meals a day w/o good reason was considered at the very least folly – or worse, idolatry (Ecc 10:16-17 w/Pro 16:26; Phi 3:19). From a physiological perspective, science continues to confirm the lack of wisdom associated w/ daily multiple meals (e.g. the relationship between insulin resistance/pre diabetes/diabetes and multiple meals a day).
7. Jesus died at the time of the evening meal reinforcing the importance of fasting unto the singular evening meal for our primary nourishment since thru it we communicate the same as it re: to Him and spiritual things (i.e. we fast from other spiritual things as our primary nourishment looking to Christ alone as the “bread from heaven” and word of God by which we singularly live; Mat 26:26-29 w/27:46-50).
8. CLOSING TAKEAWAYS
8.1. Fasting is not starving.
8.2. Fasting is not a matter of “if” but “when” for the Christian.
8.3. Fasting is necessary to self-control.
8.4. Fasting will factor into our final judgment (since it is a form of practicing righteousness).
8.5. Fasting communicates our reliance on a singular source for spiritual nourishment given the powerful theological connection between OMAD and the time of Christ’s death.
 The reason I say “most” is b/c it seems that ancient fasting did not always imply zero nourishment. Evidence from the early church suggests that small amounts of food or calories would be included during the fasting period. For example, “In the day in which you fast, you will taste nothing but bread and water. Then reckon up the price of meals of that day that you intended to have eaten, and give that amount to a widow, an orphan, or some person in need.” – Hermas (150 A.D.); “In the first place, fasting is affliction of the flesh. It makes an offering to the Lord of scantiness of food, content with a simple diet and pure drink of water.” – Tertullian (200 A.D.). As wb discussed, the OMAD diet of the Israelites was viewed as a form of fasting though they did “snack”.
 Oftentimes, 1.2. and 1.3 were interrelated. IOW: the people were fasting to accomplish both purposes (e.g. Joe 2:12-15). This dual-purpose fasting affirms LBS.
 “The phrase (“When you fast”) implies that Jesus’ disciples will fast, and when they do, this is how it is to be done” – Kent Burghuis (ETS, “Biblical Fasting”).
 Josephus speaks of meals, other than the evening meal being taken on sabbaths (Life, 54.279; See also Jubilees 50:12; Judith 8:6). Also, ancient Christian writer, Victorinus, forbid Christians from eating at all on Saturdays, “lest (they) would appear to observe Sabbath (i.e. partake of feasting) with the Jews.” Church history contains evidence of early Christians also viewing the Lord’s Day as a time when fasting was not required. By the 4th century, it was more than simply not required, it was prohibited. For example, “He who fasts on the Lord’s Day will be guilty of sin, for it is the day of the resurrection. If any member of the clergy is found to fast on the Lord’s Day or on the Sabbath day, let him be deprived [i.e. removed from office]” – Apostolic Constitutions (390 A.D.).
 “During the zenith period of Grecian and Roman civilization monogamy was not as firmly established as the rule that a health-loving man should content himself with one meal a day, and never eat till he had leisure to digest, i.e., not till the day’s work was wholly done. For more than a thousand years the one meal plan was the established rule among the civilized nations inhabiting the coast-lands of the Mediterranean. The evening repast–call it supper or dinner–was a kind of domestic festival, the reward of the day’s toil, an enjoyment which rich and poor refrained from marring by premature gratifications of their appetites. The one-meal system was [indeed] the rule in two countries [Greece and Rome] that could raise armies of men every one of whom would have made his fortune as a modern athlete–men who marched for days under a load of iron (besides clothes and provisions) that would stagger a modern porter. The Romans of the Republican age broke their fast with a biscuit and a fig or two, and took their principle meal in the cool of the evening. Among the many things that have been offered as an explanation for their physical, mental and moral decline has been their sensuous indulgence in food which came with power and riches.” – Dr. Herbert Shelton (The Hygienic System: Orthotrophy); “The Romans believed it was healthier to eat only one meal a day. They were obsessed with digestion and eating more than one meal was considered a form of gluttony. Breakfast as we know it didn’t exist for large parts of history. The Romans didn’t really eat it. As a matter of fact, breakfast was generally frowned upon. This thinking impacted on the way people ate for a very long time.” – Dr. Caroline Yeldham (“Breakfast, Lunch and Dinner: Have We Always Eaten Them?”).
 Again, voices from the early/ancient church confirm this: “The majority of Christians think that fasting should not continue beyond the ninth hour (3p.m.).” – Tertullian (200 A.D.); “We fast even to the ninth hour, or even the evening.” – Victorinus (280 A.D.). That the Jews did indeed place an emphasis on the evening meal as their primary or main meal, is picked up in Jewish writing such as Jubilees and Judith which speak of the best meal of the week being that which was prepared as the evening meal.
 It is worth noting that those times when fasting did last longer than the evening meal, it was due to extremely special circumstances (e.g.: Moses rec’g of the Law – Exo 34:28, Jesus’ testing to become the New Lawgiver – Mat 4:1-11, Elijah as God’s front-running prophet – 1Ki 19:8, the death of Israel’s first-king – 1Sa 31:13; Daniel as Israel’s prophet of redemption – Dan 10:2-6). It should also be not that such fasts also relied heavily on God’s physical protection since medical studies show such fasting to present a significant health risk – especially for children (e.g. cannibalization and shrinking of the heart, permanent heart arrhythmia). As such, “24 hr plus” fasting not prescribed via divine intervention sb weighed against possible and permanent harm to health. That being said, the anecdotal evidence supporting the ability of longer term fasting to remedy – even cure, many forms of sickness (including cancer) is abundant. See for example The Fasting Cure by Upton Sinclair. Additionally, studies have shown intermittent fasting (24 hrs or less) to be the most beneficial in terms of combating obesity or losing weight. For example, Dr. Jason Fung, M.D. states, “Intermittent fasting—in which people consume little or nothing for up to 24 hours at a time—has been shown to help some people lose weight, the same is not true of long-term fasts. One of the big-picture ideas behind intermittent fasting is called ‘hormesis’. Hormesis refers to an exposure to a relatively small amount of some stressor, which could cause the body to adapt and become more able to deal with other stressors. This is in contrast to exposure to a large stressor, which could cause harm to the body. In my opinion, short-term fasts, such as those used during intermittent fasting, would fall into the category of the small stressors which could promote health benefits. However, long-term fasts could potentially fall into the ‘large stressor’ category. Reducing food intake for weeks causes metabolism to slow, so that a person who once needed 2,000 calories per day to function might now need only 1,800. After the fast is over, it’s not clear whether the metabolism will bounce back. A recent study of contestants on The Biggest Loser, who cut their calorie intakes dramatically for the show, found the participants must now eat hundreds fewer calories each day than people of a similar size in order to maintain their reduced weights. The other reason extreme dieting was discontinued as a treatment for obese people was that the majority regained most of their weight shortly after the treatment. In a 1994 study conducted by Wadden, people on a very low-calorie diet of 420 calories per day lost more of their starting weights than people on a more reasonable diet of 1,200 calories a day. But the very low-calorie group regained much of their weight within the next year, ending up heavier than the group that didn’t starve themselves.” In this respect, consider also a recent study conducted at the Beltsville Human Nutrition Research Center (US Department of Agriculture, Agriculture Research Service, Beltsville, MD, USA). During a 6-month trial, two groups of people consumed exactly the same amount of calories differing only in the frequency w/which the meals were taken. The first group followed the traditional American plan of 3 meals/day, the other consumed all calories in 1 meal/day. Subjects on the 3 meals/day plan maintained their body weight within 4 ½ lbs of their initial weight throughout the 6-mo period. There were no significant effects. For those consuming 1 meal/day, there was significant modification of body composition, including reductions in fat mass and a significant decrease in concentrations of cortisol. Finally, it is worth considering the fact that eating OMAD tends to function as a self-regulating device for caloric intake since it is very hard to overeat (i.e. eat more calories than needed) in a single meal.
 Constant eating means a constant stream of insulin into the bloodstream. Scientific study has demonstrated a link between high insulin frequency and insulin resistance. In this respect, intermittent/daily fasting becomes a wise solution. Again quoting Dr. Jason Fung, “Intermittent fasting allows the body to lower insulin levels very low for a specified period of time longer than usual. This is precisely what helps to break, or prevent the development of insulin resistance. This is the fundamental biologic principle of homeostasis. The body likes to maintain everything within a relatively narrow range. Any prolonged stimulus leads to resistance as the body tries to resist the change. In this case, prolonged periods of high insulin will lead to insulin resistance, which will lead back to high insulin levels – in other words, insulin causes insulin resistance. So, by incorporating daily, or almost daily periods of low insulin, we are able to prevent the development of insulin resistance and even reverse relatively minor levels of resistance.”