Essential oils (the oleo portion of the plant fluid) are chemically very special in the universe of God's natural substances. Whether used in a pure concentrated state, in the natural whole juice, in the fresh plant, dissolved in a fat, or as aromatic vapors inhaled in the air, their healing power has been known and used since the most ancient of times. This is testified in Egyptian hieroglyphics dating more than 5,000 years ago. They are considered to be the first medicines of mankind and were an important part of the prescriptions of Hippocrates, the famous Greek physician whose works were published around 400 B.C.

Essential oils are composed of tiny molecules, all less than 500 atomic mass units (amu) in molecular weight. By contrast, fatty oils are composed of much larger molecules, many weighing 100 amu and more. This difference is crucial to understanding why essential oils heal and fatty oils do not, at least not is the same ways.

Because of their infinitesimal sizes, essential oil molecules can easily pass through all of the tissues of the plant and into their very cells, passing right through cell walls. Thus they bring nutrition and information into the cell and carry waste products out. The fact that they are oils (mixtures of lipid compounds) enhances this penetrating power enabling them to administer to the plant's needs from gross circulation to the internal workings of a cell.

Any essential oil placed anywhere on the body is transdermal and can reach every part of your body within minutes. Some people can put an oil, such as cinnamon, cassia, or peppermint, on the soles of their feet and taste it on their tongue in less than a minute. (CAUTION: Please don't put oils neat on sensitive areas of the skin. The bottoms of the feet are okay.)

In serving plant functions, essential oils perform many duties. They regulate plant growth, like hormones. They help in plant metabolism, like enzymes. They also provide the basis for the plant's immune system warding off undesirable viruses, bacteria, microbes, fungi, parasites, and insects. When a plant is cut, it bleeds the oleo-gum-resin into the wound which initiates healing.

Because God created the plants for us (Genesis 1:11-12, 28), their oils can serve many of the same purposes for us as they do in plants. Thus, they can support and balance our endocrine, circulatory, digestive, nervous, and reproductive systems. They can clear our sinuses and lungs to help us breathe better. They can help us metabolize our nutrients, minerals, and vitamins. They can also boost the natural defenses of our immune systems so we can fight off disease by our own abilities. And while they are friendly to us, they can be hostile to bacteria, viruses, parasites, and fungi. In this way they can attack invading offenders directly.

Many oils, applied to the skin, are also effective insect repellents. Cedarwood and myrrh are excellent in this regard, a fact that has been known and applied since ancient times. Citronella was also used as an insect repellent in Biblical times, but is not mentioned in the Bible. A few drops of mint, a Biblical oil, can be mixed with water and sprayed on rose bushes to control aphids.

And just as the bleeding resins of plants fill the wound and initiate the healing process for the plant, pouring of essential oils into cuts and wounds can accelerate healing and protect from infection because of their antiseptic capabilities. Most essential oils are microbicides to some extent. The most gentle Biblical oils are aloes (sandalwood), balm, bay, bdellium, coriander, cedarwood, cumin, cypress, frankincense, galbanum, henna, jupiter, myrrh, onycha, rue, shittim (acacia), and spikenard. The stronger antiseptic Biblical oils include anise, calcmus, cassia, cinnamon, dill, fir, hyssop, mint, mustard seed, pine, terebinth and wormwood.