On the day Jesus Christ ascended into Heaven, he prophesied that the sign of speaking in tongues would accompany those who believe. Christ's sign is an individual expression of faith that yields an inner strengthening for the individual believer: "He who speaks in a tongue edifies [builds up] himself" (1 Cor. 14:4).
Additionally, Christ intended for his sign to edify his church—the assembly of individual believers. It is by the authority of Jesus Christ that the apostle Paul provided insight regarding the operation of speaking in tongues in the church. In Paul's first letter to the city of Corinth, he explained that in a public expression of faith there is to be harmony. The Spirit of Christ is to be operated in the assembly "in a fitting and orderly way" (1 Cor. 14:40). Not everyone will manifest Christ's sign, nor will everyone bring forth an interpretation, when the church "comes together."

If the whole church¹ comes together and everyone speaks in tongues, and some who do not understand or some unbelievers come in, will they not say that you are out of your mind? . . . What then shall we say, brothers? When you come together, everyone has a hymn, or a word of instruction, a revelation, a tongue or an interpretation. All of these must be done for the strengthening of the church. If anyone speaks in a tongue, two—or at the most three—should speak, one at a time, and someone must interpret. (1 Cor. 14:23, 26, 27)

     The Christians in the church of Corinth were all speaking in tongues at once, generating chronic confusion in the assembly. Because this was not godly, Paul corrected them by indicating that only two or three Christians are needed to bring forth tongues and the corresponding interpretation. According to the apostle Paul, the one who speaks in tongues is the one who interprets: "Anyone who speaks in a tongue should pray that he may interpret what he says" (1 Cor. 14:13). Each Christian "interprets [the tongue], . . . [so that] the church [the assembly] may be edified [built up]" (1 Cor. 14:5).
     In addition to its role of building up individuals and the church, speaking in tongues is a sign for those who have yet to embrace Christ: "Tongues, then, are a sign, not for believers but for unbelievers" (1 Cor. 14:22). Through his sign, Christ draws unbelieving souls to the light of Heaven. Christ's sign of speaking in tongues is given to benefit all the Earth; it is the Lord's command that those in his church bring forth his sign. As stated by Paul: "[L]et him acknowledge that what I am writing to you is the Lord's command" (1 Cor. 14:37).
     As Christians, we owe it to the Lord, ourselves, and those who have yet to perceive the spiritual realities of this life to bring forth the sign that Christ gave to his church. "Therefore, my brothers . . . do not forbid to speak in tongues" (1 Cor. 14:39). For, wherever an individual is in their personal journey, the sign of speaking in tongues is meant to strengthen and direct the heart.

1. The word "church" itself denotes the "redeemed community." The Greek word for church is ekklesia, which means "those who are called out for a purpose." When applied to the kingdom of Christ, its definition is determined by the context. Although "church" can mean the entire world community that calls upon Christ, it can also refer to "every Church in which the character of the Church as a whole is seen in miniature," E. W. Bullinger, A Critical Lexicon and Concordance to the English and Greek New Testament (Grand Rapids, Mich.: Zondervan Publishing House, 1981), 153.
In his letter to the Corinthians, Paul draws a distinction between "the church" and "the body of Christ" (the entire body of believers on Earth). When Paul refers to the public expression of faith, he refers to the "whole church"—the assembly of Christians that gather to worship.
The Prophecy personalizes this divine sign of immortality, placing it in the grasp of the individual reader.

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