What does it mean to not let any unwholesome talk come out of your mouths (Ephesians 4:29)?

Next, it is not our deeds only that have to be considered, but our words. "Let no corrupt communication proceed out of your mouth, but that which is good to the use of edifying, that it may minister grace to the hearers." (Ver. 29.) Worthless language is to be eschewed as one rejects good-for-nothing fruit; if it were on the tongue, let the unprofitable word proceed no farther. Unclean allusion we shall find specified and forbidden in the chapter following. Here I conceive the circle is more comprehensive. Many who would neither utter nor hear impure conversation may often have to bemoan the utterance and the sanction of unsavoury discourse. Better to be silent if there be not (such is the force) something good for needful edification. The need measures the service, and love builds up instead of puffing up as knowledge does. It is equally true that "in the multitude of words there wants not sin," and that "the lips of the righteous feed many;" they "know what is acceptable;" and those who hear are refreshed and blessed.

Then (v. 29) it is not only that corrupt communication is stopped, but positive good, edification according to the need. Not only good language, but good for the occasion; and this evidently supposes the Holy Spirit's power. We have often said things, in themselves good, that were not needed for the occasion; as I recollect to have seen a philanthropist giving away food and medicines (excellent in themselves) without regard to the state of the recipients.

Verse 29. Here is seen the contrast between the old man and the new. It is one or the other which speaks; it is murmuring or giving of thanks. The matured Christian would only speak for edification; the new man, acting under the influence of the Spirit, will only take part in things which are for edification.

(V. 29). In conversation we are not to speak of those things which would corrupt the minds of the hearers, but rather to speak of that which edifies and ministers to a spirit of grace in the hearers.

The same thing may be observed in the next exhortation, "Let no corrupt communication proceed out of your mouth, but that which is good to the use of edifying, that it may minister grace to the hearers." (v. 29.) A special class of corrupt communications, such as might be expected from Gentiles who wrought "all uncleanness with greediness," is alluded to in the next chapter; but here the exhortation has a wider scope. "How can ye, being evil, speak good things?" asks our Lord of the Jews. (Matt. 12:34.) A corrupt tree can only bring forth corrupt fruit. The words, as well as the works, will bear the character of the heart from which they proceed. But it is not enough that the believer merely abstains from corrupt communications such as naturally belong to "the old man, which is corrupt according to the deceitful lusts." He has put on the new man, of which Christ is the perfect representative. Did Christ merely refrain from evil in His conversation? No; His words, like His life, "ministered grace unto the hearers." And so will the words of one who is in communion with Christ. Just so far as we walk after "the new man" will our words resemble the words of Him of whom it is written, "Grace is poured into thy lips, therefore God hath blessed thee for ever." (Ps. 45:2.)

The same thing may be observed in the next exhortation, "Let no corrupt communication proceed out of your mouth, but that which is good to the use of edifying, that it may minister grace to the hearers." (v. 29.) A special class of corrupt communications, such as might be expected from Gentiles who wrought "all uncleanness with greediness," is alluded to in the next chapter; but here the exhortation has a wider scope. "How can ye, being evil, speak good things?" asks our Lord of the Jews. (Matt. 12:34.) A corrupt tree can only bring forth corrupt fruit. The words, as well as the works, will bear the character of the heart from which they proceed. But it is not enough that the believer merely abstains from corrupt communications such as naturally belong to "the old man, which is corrupt according to the deceitful lusts." He has put on the new man, of which Christ is the perfect representative. Did Christ merely refrain from evil in His conversation? No; His words, like His life, "ministered grace unto the hearers." And so will the words of one who is in communion with Christ. Just so far as we walk after "the new man" will our words resemble the words of Him of whom it is written, "Grace is poured into thy lips, therefore God hath blessed thee for ever." (Ps. 45:2.)

Verse 29. "Let no corrupt communication proceed out of your mouth," etc. Edification is to be kept constantly in view, as the main end of the walk of those who confess that they are members of one another. And purity of speech and action can alone conduce to this. The lips of a believer have been purged from their natural uncleanness (Isa. 6:5-7), by the confession of the holy name of Jesus. Instead, therefore, of uttering perverseness, or indulging in the speech of fools, he is to speak as one who knows that both death and life are in the power of the tongue (Prov. 18:21). Our lips are no longer our own, but His who has bought us altogether for Himself. What is looked for in Christian intercourse is such an habitual remembrance of the Divine presence as shall effectually restrain the ebullitions of natural corruptions. Nothing that we cannot say confidently in that presence is fit for the ears of one another. We shall do well to remember, that if our words do not edify, they are injurious. For whatever does not savour of Christ does savour of the world; and such communications tend not to the strengthening of God's building, but to its dilapidation and destruction (1 Cor. 3:17). Now if the flesh be allowed to act in any way, it is always in derogation of the Spirit; and so it is immediately added:

But even now, in the government of God, if I am not careful of my tongue, I may come under His discipline. The seed I sow will certainly bring forth its corresponding crop by-and-by, and so will what you sow. I speak very plainly, for I get about a good deal among the saints, and I could not tell you the mischief that is done by unguarded language, and letting forth that which is not profitable. Ah, beloved, God give us all to be more careful.

I must not, as a saint, allow that which is not profitable to issue from my lips. "Let no corrupt communication proceed out of your mouth, but that which is good to the use of edifying, that it may minister grace to the hearers" (Eph. 4:29). All conversation either ministers grace to you, or it corrupts you. I do not think we ought to turn aside the keen edge of the Word of God in respect of this.

The tongue too is to be curbed. Only pure, uncontaminated words are found in Scripture, although Scripture speaks plainly about every subject pertinent to mankind's life on earth. Let us be well saturated with God's Word and avoid the impure talk so common in the world. There is so much that is good for the building up of others that our tongues should be ready always to speak such things as will minister grace to those who are listening to us (Jas.3:2).

Among the practical exhortations of Ephesians 4 is “Let no corrupt communications proceed out of your mouth, but that which is good to the use of edifying, that it may minister grace unto the hearers” (verse 29). If each one of us has received grace from Christ here is one way in which we can be of service to Him, by ministering grace to those who listen to a conversation that is honouring to Christ. In all our ways and words the grace of Christ should be seen. We may not have any of the special gifts that Christ has given to men, but we have the privilege of manifesting the features of Christ in all the details of our daily life, and so showing to others what Christ is.