Previously I presented and defined Decree vs Declare. The  following is an excerpt from The Gnosis and The Law by Tellis S. Papastavro, which contrasts a decree to prayer, and shows how a decree works, how the powers of creation are harnessed though a specialized application of speech, thought, emotion and action.

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A “Decree” is an invocative request of an individual to God or His messengers, though the voice of the outer self, for the granting of a particular need, be it ephemeral or one’s own eternal freedom. It transcends common prayer in which the appeal takes the form of an entreat. In the “Decree” it is accepted as an accomplished fact. To many of us, these words had no more meaning or significance than similar admonitions presented in the scriptures and repeated time and again.
A “Decree” is more than a vocal expression, and its efficacy is determined not only by the amount of feeling and conviction that is released through it, but also, by the clarity of the thought form held in the mental body, showing the useful purpose of the request. This triad forms the pattern around which the physical energies of the worded decree coalesce, and are best depicted when the individual, through practice, becomes still and allows the energy, radiation and power of the “I AM” presence, through the Holy Christ Self to flow into and nourish the lower bodies of the outer consciousness. To accomplish this, however, it is most essential that these lower bodies be trained to be man’s servants and not his masters. The stilling of the mental body, the quiet surging of the emotions, and the refusal to allow the etheric body to conjure up failures and disillusions of the past, are of the most importance. Then the phrase “Be still and know that I AM God” becomes real in the use of “Decrees”.
The conscious application of the “I AM” Presence, through the “Decrees” makes every call a sure instrument for an answer.
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This is very similar to the Temple Teachings. The Teachers tell us invocation of the archangels should be done in threes, Khamael, Gabriel, and a third archangel chosen according to the desired functionality. 1) Khamael is a statement of “I AM” acknowledging divine beingness, pure unapplied potential, 2) a “Holy Christ Self”, or God’s will manifest, is Gabriel (I Will), the choice to use the creative force, and 3) a clear thought form held in the mental body showing the useful purpose of the request is specified with the third archangel of the invocation.

The choice and focus on the useful purpose enough to clarify it adds another dimension to the creation and extends it in time, giving it more of a basis to build upon, and opening possibilities of differentiation and avenues of evolution of the creation. The ability to control, direct and maintain one’s focus and emotions, keep one’s body healthy, and remain positive and confident, keeps one in a divine mind-set, able and beneficent.

Perhaps my best recommendation for decrees is remember that Divine Will is the enhancement of all that is, so any of one’s creations, by decree or otherwise should intend to enhance mankind, in current and future experience.

Light, Love & Joy,
Seymour Lovejoy