Duty to Obey:
The first duty prescribed by God for His servants is the recognition of Him Who is the Dayspring of His Revelation and the Fountain of His laws, Who representeth the Godhead in both the Kingdom of His Cause and the world of creation. Whoso achieveth this duty hath attained unto all good; and whoso is deprived thereof hath gone astray, though he be the author of every righteous deed. It behoveth everyone who reacheth this most sublime station, this summit of transcendent glory, to observe every ordinance of Him Who is the Desire of the world. These twin duties are inseparable. Neither is acceptable without the other. Thus hath it been decreed by Him Who is the Source of Divine inspiration.
(Baha’u’llah: The Kitab-i-Aqdas, p. 19)

The ordinances of God have been sent down from the heaven of His most august Revelation. All must diligently observe them. Man’s supreme distinction, his real advancement, his final victory, have always depended, and will continue to depend, upon them. Whoso keepeth the commandments of God shall attain everlasting felicity.
(Baha’u’llah: Gleanings, p. 289)

Nature and Purpose:
O ye peoples of the world! Know assuredly that My commandments are the lamps of My loving providence among My servants, and the keys of My mercy for My creatures.
(Baha’u’llah: The Kitab-i-Aqdas, p. 20)

Know verily that the essence of justice and the source thereof are both embodied in the ordinances prescribed by Him Who is the Manifestation of the Self of God amongst men, if ye be of them that recognize this truth. He doth verily incarnate the highest, the infallible standard of justice unto all creation. Were His law to be such as to strike terror into the hearts of all that are in heaven and on earth, that law is naught but manifest justice. The fears and agitation which the revelation of this law provokes in men’s hearts should indeed be likened to the cries of the suckling babe weaned from his mother’s milk, if ye be of them that perceive. Were men to discover the motivating purpose of God’s Revelation, they would assuredly cast away their fears, and, with hearts filled with gratitude, rejoice with exceeding gladness.
(Baha’u’llah: Gleanings, p. 175)

`The Laws of God are not imposition of will, or of power, or pleasure, but the resolutions of truth, reason and justice.’
All men are equal before the law, which must reign absolutely.
The object of punishment is not vengeance, but the prevention of crime.
Kings must rule with wisdom and justice; prince, peer and peasant alike have equal rights to just treatment, there must be no favour shown to individuals. A judge must be no `respecter of persons’, but administer the law with strict impartiality in every case brought before him.
If a person commit a crime against you, you have not the right to forgive him; but the law must punish him in order to prevent a repetition of that same crime by others, as the pain of the individual is unimportant beside the general welfare of the people.
When perfect justice reigns in every country of the Eastern and Western World, then will the earth become a place of beauty. The dignity and equality of every servant of God will be acknowledged; the ideal of the solidarity of the human race, the true brotherhood of man, will be realized; and the glorious light of the Sun of Truth will illumine the souls of all men.
(`Abdu’l-Baha: Paris Talks, pp. 154-155)

The Law must reign, and not the individual; thus will the world become a place of beauty and true brotherhood will be realized. Having attained solidarity, men will have found truth.
(`Abdu’l-Baha: Paris Talks, p. 132)

If the edifice of religion shakes and totters, commotion and chaos will ensue and the order of things will be utterly upset, for in the world of mankind there are two safeguards that protect man from wrongdoing. One is the law which punishes the criminal; but the law prevents only the manifest crime and not the concealed sin; whereas the ideal safeguard, namely, the religion of God, prevents both the manifest and the concealed crime, trains man, educates morals, compels the adoption of virtues and is the all-inclusive power which guarantees the felicity of the world of mankind.
(`Abdu’l-Baha: Selections … `Abdu’l-Baha, pp. 302-303)

All religious laws conform to reason, and are suited to the people for whom they are framed, and for the age in which they are to be obeyed.
Religion has two main parts:
(1) The Spiritual.
(2) The Practical.
The spiritual part never changes. All the Manifestations of God and His Prophets have taught the same truths and given the same spiritual law. They all teach the one code of morality. There is no division in the truth. The Sun has sent forth many rays to illumine human intelligence, the light is always the same.
The practical part of religion deals with exterior forms and ceremonies, and with modes of punishment for certain offences. This is the material side of the law, and guides the customs and manners of the people.
(`Abdu’l-Baha: Paris Talks, pp. 141-142)

The Most Holy Book:
While in prison We have revealed a Book which We have entitled `The Most Holy Book’. We have enacted laws therein and adorned it with the commandments of thy Lord, Who exerciseth authority over all that are in the heavens and on the earth. Say: Take hold of it, O people, and observe that which hath been sent down in it of the wondrous precepts of your Lord, the Forgiving, the Bountiful. It will truly prosper you both in this world and in the next and will purge you of whatsoever ill beseemeth you.
(Baha’u’llah: Tablets of Baha’u’llah, p. 262)

As to the laws themselves, a careful scrutiny discloses that they govern three areas: the individual’s relationship to God, physical and spiritual matters which benefit the individual directly, and relations among individuals and between the individual and society. They can be grouped under the following headings: prayer and fasting; laws of personal status governing marriage, divorce and inheritance; a range of other laws, ordinances and prohibitions, as well as exhortations; and the abrogation of specific laws and ordinances of previous Dispensations.
(The Universal House of Justice: Aqdas: Other Sections, p. 4)

Some Specific Laws:
We have commanded you to pray and fast from the beginning of maturity; this is ordained by God, your Lord and the Lord of your forefathers.
(Baha’u’llah: The Kitab-i-Aqdas, p. 22)

Recite ye the verses of God every morn and eventide.
(Baha’u’llah: The Kitab-i-Aqdas, p. 73)

It is incumbent upon each one of you to engage in some occupation – such as a craft, a trade or the like. We have exalted your engagement in such work to the rank of worship of the one true God. Reflect, O people, on the grace and blessings of your Lord, and yield Him thanks at eventide and dawn. Waste not your hours in idleness and sloth, but occupy yourselves with what will profit you and others.
(Baha’u’llah: The Kitab-i-Aqdas, p. 30)

In every country where any of this people [Baha’is] reside, they must behave towards the government of that country with loyalty, honesty and truthfulness.
(Baha’u’llah: Tablets of Baha’u’llah, pp. 22-23)

Unto everyone hath been enjoined the writing of a will.
(Baha’u’llah: The Kitab-i-Aqdas, p. 59)

Resort ye, in times of sickness, to competent physicians; We have not set aside the use of material means, rather have We confirmed it through this Pen, which God hath made to be the Dawning-place of His shining and glorious Cause.
(Baha’u’llah: The Kitab-i-Aqdas, p. 60)

Gambling and the use of opium have been forbidden unto you.
(Baha’u’llah: The Kitab-i-Aqdas, p. 75)

Ye have been forbidden to commit murder or adultery, or to engage in backbiting or calumny; shun ye, then, what hath been prohibited in the holy Books and Tablets.
(Baha’u’llah: The Kitab-i-Aqdas, p. 26)

Ye have been forbidden in the Book of God to engage in contention and conflict, to strike another, or to commit similar acts whereby hearts and souls may be saddened.
(Baha’u’llah: The Kitab-i-Aqdas, pp. 72-73)

There must be special laws made, dealing with these extremes of riches and of want. The members of the Government should consider the laws of God when they are framing plans for the ruling of the people. The general rights of mankind must be guarded and preserved.
(`Abdu’l-Baha: Paris Talks, pp. 153-154)