The question raised here is whether it is proper for a pastor to be in secret contact with a member of another pastor's congregation. To be more specific, the pastors are of the same Confessional Lutheran denomination as the members they are in contact with. And to be even more specific, the pastors are speaking with the congregation members about their own pastor.
This writer knows of at least a half-a-dozen such situations within one particular Confessional Lutheran denomination. And each of those contacts has greatly disturbed the ministry of the word at those congregations by setting the members against their own pastor.
This writer also knows of 3 such incidents where the congregations have been incited to remove their pastors without Scriptural grounds.
What are Scriptural grounds?
1) If a pastor is a persistent teacher of false doctrine, for Scriputre directs us to "note those who cause divisions and offenses, contrary to the doctrine which you learned, and avoid them." (Romans 16:17)
2) If a pastor is living in open sin. For God says through His apostle Paul "But now I have written to you not to keep company with anyone named a brother, who is sexually immoral, or covetous, or an idolater, or a reviler, or a drunkard, or an extortioner—not even to eat with such a person." (I Cor. 5:11)
3) If a pastor is not doing his duty in feeding the flock of Christ given to him by God with the Word and Sacraments. For Scripture teaches that a shepherd must not only be "able to teach" (I Tim 3:2; 2 Tim 2:2 and 24) but also "“Woe to the shepherds of Israel who feed themselves! Should not the shepherds feed the flocks?" (Ezk. 34:2)
But neither the congregations nor the meddling ministers, the sneak preachers ever bothered to publicly show these men guilty of these faults. "19 And this is the condemnation, that the light has come into the world, and men loved darkness rather than light, because their deeds were evil. 20 For everyone practicing evil hates the light and does not come to the light, lest his deeds should be exposed. " (John 3)
Rather they worked in secret, without the knowledge of the blameless pastors. They usurped their calls and have poisoned and scattered their flocks.
They have sinned against God and His Church. They have defiled the flock, and-being worse than hirelings-they have raged among the flocks as wolves.
To those false prophets God says:
“You have scattered My flock, driven them away, and not attended to them. Behold, I will attend to you for the evil of your doings,” says the LORD. (Jeremiah 23:2)
To those congregations who listen to these sneak preachers, God says:
16 Thus says the LORD of hosts:
“ Do not listen to the words of the prophets who prophesy to you.
They make you worthless;
They speak a vision of their own heart,
Not from the mouth of the LORD.
17 They continually say to those who despise Me,
‘ The LORD has said, “You shall have peace”’;
And to everyone who walks according to the dictates of his own heart, they say,
‘ No evil shall come upon you.’”
18 For who has stood in the counsel of the LORD,
And has perceived and heard His word?
Who has marked His word and heard it?
19 Behold, a whirlwind of the LORD has gone forth in fury—
A violent whirlwind!
It will fall violently on the head of the wicked.
20 The anger of the LORD will not turn back
Until He has executed and performed the thoughts of His heart.
In the latter days you will understand it perfectly.
21 “ I have not sent these prophets, yet they ran.
I have not spoken to them, yet they prophesied.
Turn, be reconciled to your own true shepherd, placed there by God through the Call He extended. Your pastor is there because God placed him there. No other pastor, denominational or synodical official has any right to usurp that call.
The Relationship which Christ, the Bridegroom, has established to His Church is throuh His called Shepherd, the pastor. By God's call the pastor represents the Holy Bridegroom to you, the bride of Christ. "What God has joined together, let not man put asunder."