What the Scriptures Say About: Fasting

When your stomach begins to growl halfway through fast and testimony meeting, you probably do not think of fasting as rejoicing, yet this is the way fasting has been scripturally defined: “Verily, this is fasting and prayer, or in other words, rejoicing and prayer.” (D&C 59:14.) Rejoicing means to express joy, and joy is the reason for man’s existence. (2 Ne. 2:25.) Fasting, then, is an activity that brings us back to the state of being for which we were created.

Our ability to rejoice on fast Sunday or at any other time we choose to fast is dependent on a number of things. One of these is our purpose in fasting.

Why Fast?

The scriptures give many reasons for fasting. Jesus explained to his disciples, when they were unable to cast a devil from a suffering man, that there is a level of spiritual power obtainable only by “prayer and fasting.” (Matt. 17:14–21.)

The sons of Mosiah reported that during their missions to the Lamanites they “had given themselves to much prayer, and fasting; therefore they had the spirit of prophecy, and the spirit of revelation, and when they taught, they taught with power and authority of God.” (Alma 17:3.) Alma, who had obtained a basic testimony of the truth of the gospel at the time of his conversion, testified that he later “fasted and prayed many days that [he] might know” of the truth of certain points of gospel doctrine. He was given a testimony “by the Holy Spirit of God,” which also gave him “the spirit of revelation.” (Alma 5:44–47.)

Fasting helps develop self-mastery and discipline, as noted in the following expressions: “I humbled my soul with fasting” (Ps. 35:13), and “I … chastened my soul with fasting” (Ps. 69:10).

The prophet Amaleki linked fasting with salvation when he exhorted his people to “continue in fasting and praying, and endure to the end; and as the Lord liveth ye will be saved.” (Omni 1:26.)

By far the most important reason for fasting is that the Lord has commanded it in latter-day revelation: “Also, I give unto you a commandment that ye shall continue in prayer and fasting from this time forth.” (D&C 88:76.)

When to Fast

Fasting is most often thought of in conjunction with worship services (Moro. 6:5; 3 Ne. 27:1; 4 Ne. 1:12), and it is in this sense that many observe the fast today. They fast on the day assigned for all members of a given ward or branch to fast and donate the money for the meals they miss to the needy. On each Sabbath day food should be prepared simply and in a manner not to detract from the spirit of the occasion, and physical labor and many everyday activities should be avoided. (D&C 59:13.)

When members of the Church are oppressed by unbelievers, they can fast and pray that the hearts of their oppressors might be changed. One of the most spectacular examples of this is found in Mosiah when the elder Alma and the priests “fasted and prayed for the space of two days and two nights” that the Lord would heal Alma physically and spiritually. (Mosiah 27:22–23.)

Later when Alma was the high priest of the church, the Lord commanded the members to “gather themselves together oft, and join in fasting and mighty prayer in behalf of … those who knew not God.” (Alma 6:6.)

Beautiful Queen Esther and her people fasted three days and nights for deliverance from the oppressive decrees of the Persian king, and they were delivered. (Esth. 4:16.)

Cornelius fasted when he wanted to know the truth, and Peter was sent to teach him the gospel. (Acts 10:30–33.)

Certain leaders in Antioch fasted to determine those who should be called and set apart as missionaries. (Acts 13:1–3.)

Fasting is mentioned in times of both war and death. When they were victorious over their enemies, the faithful Nephites “did fast much and pray much, and they did worship God with exceeding great joy.” (Alma 45:1.) But victories are won at the expense of many lives, and fasting seems to have helped bind up the wounds of the mourners and bring a return of peace: “… it came to pass after they had buried their dead, and also after the days of fasting, and mourning, and prayer … there began to be continual peace throughout all the land.” (Alma 30:2.) On another occasion the Nephites “did assemble themselves together to mourn and to fast, at the burial of the great chief judge who had been slain.” (Hel. 9:10.)

Since fasting is basic to spiritual power, testimony, self-mastery, and one’s general spiritual well-being, it follows that fasting is essential also in obtaining a forgiveness when one has sinned. After the appearance of the angel to Alma the Younger, he was forced to fast for three days for he could not even open his mouth, and it was during this time that his soul was “harrowed up to the greatest degree and racked with all [his] sins.” In the midst of his torment he remembered his father’s words about Jesus Christ and his atonement, and this thought grew until it replaced the memory of his sins: “And oh, what joy, and what marvelous light [he] did behold; yea, [his] soul was filled with joy as exceeding as was [his] pain!” (Alma 36:10–20.) Paul at the time of his miraculous conversion had also been without food for three days. (Acts 9:9.)

Fasting, however, cannot be expected to accomplish a thing when it is contrary to the will of the Lord. David fasted and prayed for the life of his afflicted son, but in this case the child died after seven days of illness. (2 Sam. 12:15–23.)

How to Fast

Jesus explained that fasting should be done without fanfare; and not “of a sad countenance” so as to “appear unto men to fast … But thou, when thou fastest, anoint thine head, and wash thy face; That thou appear not unto men to fast. …” (Matt. 6:16–18; see also 3 Ne. 13:16–18.)

Paul suggested that fasting should include abstinence from other physical pleasures in addition to food and drink. (1 Cor. 7:5.)

The length of the fast is not prescribed by scripture. Moses is said to have fasted “forty days and forty nights; he did neither eat bread, nor drink water.” (Ex. 34:28.) Jesus also “fasted forty days and forty nights [and] was afterward an hungred.” (Matt. 4:2.) In most other instances where a specified time is given, it is limited to about two or three days. The scriptures do specify that one should fast oft. Generally a regular fast of a few meals would be more effective for most of us than trying to fast for long periods of time.


The prophet Isaiah capsuled the subject of fasting very accurately.

He began by pointing out to his people that some of their fasts were not acceptable because they were done for selfish and self-righteous reasons. These same people complained that the Lord ignored them and did not respond to their fasts. The prophet, speaking for the Lord, explained why:

“Behold, ye fast for strife and debate, and to smite with the fist of wickedness: ye shall not fast as ye do this day, to make your voice to be heard on high.

“Is it such a fast that I have chosen? A day for a man to afflict his soul? is it to bow down his head as a bulrush, and to spread sackcloth and ashes under him? wilt thou call this a fast, and an acceptable day to the Lord?” (Isa. 58:4–5.)

Isaiah then explained what the right reasons were for fasting and that beneficial results could come from it:

“Is not this the fast that I have chosen? to loose the bands of wickedness, to undo the heavy burdens, and to let the oppressed go free, and that ye break every yoke?

“Is it not to deal thy bread to the hungry, and that thou bring the poor that are cast out to thy house? when thou seest the naked, that thou cover him; and that thou hide not thyself from thine own flesh?”

From such a fast come such blessings as improved health of body and soul, answers to prayers, and guidance in temporal and spiritual things:

“Then shall thy light break forth as the morning, and thine health shall spring forth speedily: and thy righteousness shall go before thee; the glory of the Lord shall be thy rereward.

“Then shalt thou call, and the Lord shall answer; thou shalt cry, and he shall say, Here I am. If thou take away from the midst of thee the yoke, the putting forth of the finger, and speaking vanity;

“And if thou draw out thy soul to the hungry, and satisfy the afflicted soul; then shall thy light rise in obscurity, and thy darkness be as the noonday:

“And the Lord shall guide thee continually, and satisfy thy soul in drought, and make fat thy bones: and thou shalt be like a watered garden, and like a spring of water, whose waters fail not.” (Isa. 58:6–11.)

Indeed, this catalog of blessings offered to those who fast for the right reasons, at the right time, and in the right way is reason for rejoicing.