Man was created not only in the inward image of the Triune God but also after Their (outward) likeness. This likeness is the form of God's being (Phil. 2:6), the expression of the essence and nature of God's person (Heb. 1:3). Christ existed in the form of God, that is, in the likeness of God. When He became a man, He laid aside the likeness of God and took the form of a slave (Phil. 2:7). He laid aside the form of God, but He did not lay aside the essence of God. Christ laid aside the outward likeness, the form of God's being. The form of God's being is the expression of the essence and nature of God's person. Hebrews 1:3 says, "Who [Christ], being the effulgence of His glory and the impress of His substance..." The essence of God is something within God Himself. This essence needs an outward expression, an impress, like the impress of a seal. Christ is the impress, the outward form, of God's being.
Man was created as the highest of the created life. God's creation is in the way of life. According to Genesis 1, the life God created was of three categories: plant life, animal life, and human life. The first thing created on this earth by God through His Spirit was the plant life, including the grass, the trees, and the flowers. This is the life without any consciousness, the lowest form of created life. After the plant life, God created the animal life. This life is on a higher level and is stronger than the plant life. The animal life has consciousness, but the plant life does not. Even the smallest animals, such as the ants, are very conscious. Eventually, God's creation reached the highest level with the creation of human life. The human life has the highest consciousness. Although many of the animals are very clever and skillful, none of these animals can speak human language. Yet human beings have the ability to learn to speak any kind of human language. If an animal such as Balaam's donkey (Num. 22:27-30) speaks human language, that is a miracle. Yet man can speak many different languages. This is an indication that man's life is the highest among the created lives.
Man as the highest of created life was created after God's kind (Gen. 1:26-27). Genesis 1 tells us that all the plants were created after their kind (vv. 11-12). Today, if you plant a peach tree, it will produce peaches. In the same way, if you plant an almond tree, it will produce almonds, not bananas. It is the same with the animal life (vv. 21, 24-25). Crabs in the water produce other crabs after their kind. Crabs cannot produce turtles. Crabs are in one family, and plants are in another family. Mankind, however, is after God's kind.
When two trees are grafted together, they must be very similar or they cannot grow together. For example, a branch from a peach tree cannot be grafted into an apple tree. However, a branch from a peach tree of one variety can grow together with a peach tree of a different variety. The two can grow together because they are of the same kind. In the same way, we can be grafted into God (Rom. 11:17-24) and grow together with Him (6:5) because we and God are of the same kind.