“Abide in me, and I in you. As the branch cannot bear fruit of itself, except it abide in the vine; no more can ye, except ye abide in me. I am the vine, ye are the branches: he that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing.” John 15:4–5
We confess that we know God by two means: the most elegant book of creation and His most Holy Word. In His infinite wisdom, the Holy Spirit has incorporated many aspects of creation into His Word. When meditating on the nature of these items in the light of Scripture, it often seems that their roles in the natural world were created for the express purpose of teaching spiritual truths.
One prominent example of the coordination between natural revelation and the revealed Word is that of fruit(s). In Scripture, fruits are bookends to the canon of Scripture, first appearing in Genesis 1:11 (…and the fruit tree yielding fruit after his kind”) and last appearing in Revelation 22:2 (“In the midst of the street of it, and on either side of the river, was there the tree of life, which bare twelve manner of fruits, and yielded her fruit every month.”). In between these chapters, fruits or fruitfulness are mentioned at least 250 more times. Scripture refers to many creatures as fruits: edible products of trees (Gen. 1:11), edible products of vines (2 Kings 19:29), livestock (Deut. 28:4), children (Ps. 127:3), the entire complement of goods produced by a land (Lev. 25:19), and the abundance of living things that arise from God’s sovereign care of the earth (Ps. 104:13). Men’s actions, whether good or evil (Rom. 7:4, 5), and the results of men’s actions, whether good (Isa. 3:10) or evil (Hos. 10:13), are also described as fruits. Significant among the many remaining biblical uses of fruits is the fruit brought forth by the preached gospel (Rom. 1:13).
This article focuses on those edible products that we call “fruits” today. So, what is a fruit? Colloquially, fruit is the category of produce that can be eaten raw, contains seeds, and tastes sweet or sour. Using this definition, apples, oranges, cherries, grapes, and watermelon are correctly considered common fruits. As is often the case, a more technical definition exists for scientific use. The textbook definition of a fruit is “a mature, ripened ovary (or group of ovaries), containing the seeds of a particular type of plant, called an angiosperm.” In order to understand this definition, we first need to understand a few details related to plant anatomy and reproduction—details that will allow us to marvel at the greatness of the Creator by observing the biological complexity required for the production of a common snack.
Angiosperms are plants that produce flowers, and the ovary of these plants is considered part of the flower and is typically located at the base of the flower petals. Ovaries contain another structure inside them called an ovule. Ovules are the flower structures where the female reproductive cells are produced and stored, and multiple ovules can be located in a single ovary. The female reproductive cells of angiosperms are notable in that they consist of a single egg, a “central cell” that contains double the genetic information as normal cells, and several other supporting cells. So, the egg and the central cell are inside an ovule, one or more of which are inside an ovary, which is underneath the flower petals. However, the simple development of an ovary, ovules, and eggs does not result in the development of a fruit. Additional structures are important for understanding what fruit are and how they are formed. One such structure is a long extension of the ovary called a style, which extends up and out of the flower. The specialized end of the style is another structure, called a stigma. It is the stigma that receives the male reproductive cells, which are also necessary for the production of fruit.
Male reproductive cells are contained inside pollen grains and consist of two cells, one called a vegetative cell and one called a generative cell. When a pollen grain lands on a stigma, the pollen grain is activated, causing the vegetative cell to develop into a long structure of its own that travels down the style, into the ovary, and then into an ovule. This long structure is called a pollen tube, and is remarkable in that it can grow at a rate of one centimeter per hour, grow up to a few inches long, and is made up of only a single cell. While the pollen tube is developing, it is carrying the generative cell, which splits into two cells, now called sperm cells. When the pollen tube enters the ovule, the two sperm cells exit the pollen tube, enter the ovule, and engage in a process called double fertilization. This process is called “double” fertilization, because, instead of a single sperm cell combining with a single egg cell, one of the sperm cells combines with the single egg while the other sperm cell combines with the central cell. Following double fertilization, the combined egg and sperm will develop into the plant embryo, while the combined central cell and sperm will develop into a nutrient source, called the endosperm, which feeds the developing embryo.
The ovule containing the embryo and endosperm will now develop into a seed, and the ovary surrounding the ovule (or multiple ovules, depending on the type of plant) will develop into the fruit. Seed development includes the growth and division of the embryo cells inside the seed, as well as the development of a tough coat around the outside of the seed. Additionally, combinations of chemicals are deposited on the outside of the seed that will regulate how much water can pass into or out of the seed and what type of environmental conditions will induce seed germination. When the embryo inside the seed reaches a mature state (mature for an embryo), the seed and embryo become dry and enter a state of dormancy. Dormancy in seeds is an extreme decline of the embryo’s metabolism, such that only the most basic cellular process required for the embryo cells to stay alive are active, and even these processes occur slowly.
The transformation of the ovary into fruit occurs while embryos are maturing and seeds are developing. However, it is at this point that generalizations across fruit types become difficult, as different types of fruits undergo different—even opposite—developmental processes. One process that is common to all fruits is the reorganization of the ovary wall into the fruit wall, or pericarp. Yet, even pericarps differ widely between fruit types. Then fruits begin to take in and store water or release water, depending on the fruit type. Existing internal ovary structural elements are expanded and reorganized or diminished and expunged, again depending on fruit type. Finally, molecules that provide fruits with their characteristic tastes—such as sugars and acids—and aromas are produced and stored.
Here, in order to underscore just how widely varied fruits can be when following our more technical definition, it may be useful to mention some items that are technically fruits. Apples, tomatoes, coconuts, plums, dandelion “seeds,” chili peppers, acorns, olives, beans, grapefruit, and cockleburs are all fruits by our technical definition. With just this small sampling of fruits, we can see how different the processes of pericarp formation, water management, structural development, and flavor and aroma molecule generation can be. For example, few people would confuse the taste of a chili pepper with that of a plum. Anyone who has poked a grapefruit half with a spoon knows that they are literally bursting with stored water. On the other hand, dandelion fruit are designed to float on gentle breezes, and therefore, do not possess much water weight. Tomato pericarp (which is just below the tomato “skin”) is soft enough to bite through with virtually no effort. Yet, the pericarp of coconuts is dense enough to require a rock or machete to break through. In addition, the portion of a coconut that we eat is actually all endosperm. Both coconut milk and coconut meat are endosperm, and therefore the endosperm of coconuts constitutes a large portion of the fruit. By comparison, the endosperm of fruits like apples is only a tiny portion contained inside the seeds. Many fruit categorizations have been devised based on shared architectural similarities. For example, “aggregate fruits” like blackberries and raspberries develop from multiple ovaries of a single flower, while “multiple fruits” like pineapples are formed from two or more flowers merging together. When following the definitions for these categories of fruits, it is interesting to note that tomatoes and chili peppers are berries, while raspberries are not.
In order for us to enjoy a fruit, each of the processes described above must take place, from the development of the unique cells inside the ovule, to the journey of a pollen grain to the stigma, to the remarkable transformation of a pollen grain into a long tube perfect for the delivery of two sperm into the ovule, to the fascinating process of double fertilization, to embryo formation, to seed development, and finally to fruit development around the seeds. Today, we can even enjoy the fruits of sovereignly directed technological advances that allow for the production of seedless fruit varieties, so that we do not have to suffer the burden of swallowing the occasional seed as we dine on our fruit salads.
While the fruits listed above are fairly common in the United States, many hundreds of fruit varieties exist across the world. Fruits such as pitaya and rambutan are becoming more widely available, and readers of the Standard Bearer may be familiar with durian, to name just a few “exotic” fruits. The expansion of fruit hybridization continues to introduce new fruit varieties into the market too (you may never taste a fruit sweeter than a nectaplum!).
In this context, it is interesting to speculate on the different types of fruit that were commonly eaten by biblical characters. Was the variety of fruits available to Adam immediately restricted after the Fall (other than the fruit of the tree of life, that is)? Did Noah notice a difference in varieties that returned after the flood? Did Solomon import fruit trees from faraway lands? What fruits did Jesus commonly eat? Did Paul find a new variety of fruit that he favored on one of his missionary journeys? We know that most of these individuals ate grapes and olives, and visitors to the tabernacle or Solomon’s temple would have been familiar with pomegranates (figs, it turns out, are not fruits according to our technical definition). The important point, though, is not so much which types of fruit they ate, but rather that throughout biblical history God’s people were intimately familiar with fruit, as is evidenced by the profound spiritual truths communicated to us by way of the example of fruit.
The focus of this article is not to delve into these rich spiritual truths. However, a very profitable Sunday afternoon can be had reviewing and meditating on these concepts. Thanks be to God for providing us with fruit that we can enjoy, and so that we can readily understand precious truths such as the one presented in the opening verse of this article.