Life may be viewed under two categories -- physical life and spiritual life. (a) All biological organisms are characterized by physical "life." A living creature has independent movement, processes food and oxygen, reproduces, etc. Life is a mystery that science cannot explain. It is a "gift" from God (Acts 17:25; 1 Tim. 6:13). It has been estimated that the probability of "life" starting itself is on the order of one in ten to the two-billionth power -- which means it simply could not happen. Human life is sacred because man and woman exist in the image of God (Gen. 1:26; 9:6). It is therefore wrong to arbitrarily (i.e., without authority) take human life. Physical life is temporal due to the introduction of sin (Gen. 2:17; Rom. 5:12; 6:23). (b) Spiritual life is the state of being united with God in a Father/child relationship. The Ephesian saints, prior to their conversion to Christ, had been "dead" in their trespasses and sins, but they were "made alive" by their union with the Lord (Eph. 2:1, 5). In many passages "life" is used as the equivalent of "salvation." "For God so loved the world, that he gave his only begotten Son, that whosoever believeth on him should not perish, but have eternal life. For God sent not the Son into the world to judge the world; but that the world through him might be saved" (Jn. 3:16-17). Note the parallel expressions. Spiritual life is received when one is raised from the water of baptism (Rom. 6:4). The redeemed person's spiritual life, or communion with God, extends into heaven itself -- for all who remain faithful (2 Cor. 5:4; 2 Tim. 1:10; Rev. 2:10). In the eternal order, even the wicked continue to "live" (i.e., exist), though they do not enjoy "eternal life" (Mt. 10:28; 25:46; Mk. 9:48).