"Speaking the truth, in love, we are to grow up in all aspects into Him, who is the head, even Christ," (Eph. 4:15); "Faithful are the wounds of a friend," (Prov. 27:6). Faithfulness in speaking the truth is rare, these days. And among those who have a bent for ruthlessly speaking the truth, doing so in love is even more rare. Only as a believer "grows up," taking God and His Word more and more seriously, does he or she find the balance of truth with love.
In the context of Eph. 4:15, Paul is admonishing the believers in Ephesus to move on to maturity, no longer acting as gullible children who are led astray by the cunning of false teachers. Instead, they (and we) are to learn to speak the Word (John 17:17) in love.
This love in which we are to speak the truth is not some sentimental or superficial feeling of endearment. Indeed, the friend may be wounded in the process. This love is one which seeks the good of the friend beyond the possible hurt the truth may produce. It is not unlike the spiritual surgery which the Holy Spirit performs, in convicting us of sin. Often He must cut deeply, and our flesh detests His knife, but it is always needed for our holiness and usability. The mature Christian yearns for the scalpel, willing to be pained for the purpose of producing more fruit.
Great grace is needed, both for the speaking and the receiving of biblical truth, with sensitivity to timing and wording being crucial.
May God grant us this grace, and with it the determination to grow up in all ways, in Him.