If we deliberately keep on sinning after we have received the knowledge of the truth, no sacrifice for sins is left, but only a fearful expectation of judgment and of raging fire that will consume the enemies of God.
-Hebrews 10:26-27, NIV
Divorce is not always a sin.
If it was, then the author of Jeremiah was suggesting God sinned when ascribing the metaphorical action of divorce to God (see Jeremiah 3:8).
Circumstances exist where divorce is not sin.
But adultery is always sin.
“Thou shalt not commit adultery” (Exodus 20:14, KJV) has not changed since the days of Moses when this law from the Ten Commandments was given.
So, the application of the truth is simple taken in conjunction with the instruction from Hebrews 10:26-27:
Someone continuing in adultery is someone who ought to expect God’s judgment and hell-fire.
So, the greater spiritual peril exists for those engaging in adultery not those engaging in divorce–which may or may not be sin depending on the circumstances.
Divorce is not without its issues just as declaring bankruptcy for a defunct business is not without its trouble. But spiritual triage suggests godly pastors and other Christian leaders ought to take adultery and the need for repentance from such sin as the greater problem.