Ephesians 4:14, 15

"As a result, we are no longer to be children, tossed here and there by waves, and carried about by every wind of doctrine, by the trickery of men, by craftiness in deceitful scheming;
but speaking the truth in love, we are to grow up in all aspects into Him, Who is the Head, even Christ."

One of the greatest grievances to God (and, by extension, to those He calls as pastor/teachers) is believers who should be mature but still do not have their senses trained to discern spiritual danger.  Paul knew the intense need for Christians (1) to move beyond gullible immaturity, becoming spiritual adults who are consistently stable; (2) to be alert to the schemes of the enemy; and (3) whose speech is replete with the truth, graciously given.

(1)  Employing nautical imagery, Paul likens the immature Christian to a child adrift upon a storm-tossed sea.  It is an ocean of doctrines, vast and varied, driven by the enemy's spirits for the destruction of the child's faith and testimony.  To be anchored against such forces of drift, to become spiritually grounded in sound doctrine, requires ongoing diligence in study of the Scriptures for the purpose of increasing knowledge of the Lord Jesus (John 5:39).  The greater the saturation of the truth, the greater the sensitivity to the false.  

(2)  Christendom is rife with false teaching and teachers.  As in Paul's day, so today "works righteousness" in a myriad of forms permeates religious life.  The most devastating teaching is not coming from the more obvious doctrine of cults and the like, but from the seemingly-orthodox ministries.  Appealing to Scripture (giving the impression of soundness) interpreted to support their "grace plus" perspective, the false teachers render the cross of Christ needless, point their followers to themselves for authority, and do immeasurable damage to the body of Christ, as they give the false impression that works are necessary for salvation.  

(3)  For good or ill, everyone's mouth speaks from that which fills his heart (Luke 6:45).  That upon which we think, meditate, ponder and dwell will be spoken.  To mature, we must think the truth, speak the truth, and live the truth.  No one produces godly fruit from error. The primary tool God has provided for this life-long quest is His Word (John 17:17), which is to be spoken in the power of the Holy Spirit, for the exposure and silencing of false teachers (Hebrews 4:12; Titus 1:11).  In the delegated authority of our Head (Matthew 28:18), we are to contend earnestly for the faith which was once for all delivered to the saints (Jude 3), speaking Scriptural truth with the sincere desire for our hearers' salvation.  

May our God grant grace to obey His Word, sensitive to His blessed Holy Spirit, as we have opportunity to speak His truth in love.