Some Ans. Questions 2014 by -'Abdu'l-Bahá- 1 Para

Answer: The wisdom of the appearance of the spirit in the body is this: The human spirit is a divine trust which must traverse every degree, for traversing and passing through the degrees of existence is the means of its acquiring perfections. So, for example, when a man travels in an orderly and methodical manner through many different countries and regions, this will most certainly be the means of acquiring perfections, for he will see at first hand various sites, scenes, and regions; learn about the affairs and circumstances of other nations; become familiar with the geography of other lands; acquaint himself with their arts and wonders; become informed of the customs, conduct, and character of their inhabitants; witness the civilization and the advancements of the time; and be apprised of the manner of government, the capacity, and the receptivity of each country. In the same way, when the human spirit traverses the degrees of existence and attains each degree and station- even that of the body- it will assuredly acquire perfections (52:2)

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