How did the tree of life signify Christ?

VI. What was interdicted to them in that pristine state is now not only made lawful to us, but also commanded and promised in the state of grace (in which easy access is given to us to the heavenly paradise and to Christ, the true tree of life). This is the truth and mystery shadowed in this ancient type: the tree of life—not earthly, but heavenly; not material and irrational (alogos), but mystical and rational; not only significative and sealing of life, but truly the bestower of it. “In him was life” (Jn. 1:4, i.e., the fountain and cause of all life). This life is as much natural in the world (because in him we live and move and have our being, Acts 17:28), as spiritual in the church through grace (because as Mediator, he is the prince of life giving life to the world and eternal life in heaven by glory; for he is “the resurrection and the life” who will most certainly bestow upon his own eternal life). Truly he is the only tree because no one except Christ is the author of eternal life (nor is there salvation in any other, Acts 4:12). No one except Christ is in the midst of paradise (Rev. 2:7) and of the street of the city (Rev. 22:2). Christ is in the midst of the church (as a more honorable and suitable place) to be near all and diffuse his vivifying power among all; to be seen by all, as the center in which all the lines of faith and love ought to meet, that they may acquiesce in him. The fruit-bearing tree (Rev. 2:7), which bears the sweetest and most exquisite fruit for the support of believers (Cant. 2:3), bears twelve kinds of them (Rev. 22:2), i.e., the most abundant and richest, sufficing for the twelve tribes of Israel (i.e., for all the members of the church, which from his fullness draw all gifts necessary for them). It bears them every month (i.e., perpetually) because the power and efficacy of the righteousness and spirit of Christ are perpetual and unceasing for the consolation and sanctification of believers. Its leaves (never falling and perpetually green) are appointed for the healing of the nations because it has the virtue not only of aliment (to feed our souls), but also of medicine (most healthful to cure all our diseases, Is. 53:5; Mt. 11:28). VII. Hence it is evident that these two trees of paradise are not free from mystery. For as the first was a sacrament of trial (which prescribed to man his duty) and the second a symbol of the reward (by which God wished to remunerate his obedience), so each shadowed forth to us in the best manner, the mode of God’s acting in the church by commands and promises. The former prescribed to man his duty and explored his obedience (well signified by the tree of the knowledge of good and evil). The latter exhibited the blessing and most ample reward of God by which he wishes to crown our obedience (fitly expressed by the tree of life). Second, the law and the gospel can also be contained under this double symbol. For the law (as the tree of the knowledge of good and evil) is given to us as a trial of obedience and by sin (no less than that) is made the occasion of death and the minister of condemnation. The gospel, however, is the saving and quickening tree of life because it is “the word of life” (Jn. 6:68). Third, the former exhibits the image of Adam from whom sin and death flowed; however the latter exhibits Christ from whom righteousness and life arise (1 Cor. 15:22).

 

Francis Turretin, Institutes of Elenctic Theology, 8.5.7, ed. James T. Dennison Jr., trans. George Musgrave Giger, vol. 1 (Phillipsburg, NJ: P&R Publishing, 1992-1997), 582