The bishops commended ECOWAS for its recent intervention in The Gambia, whose president of 22 years, Yahya Jammeh, refused to accept the results of a December 2016 election in which he was defeated.
This resulted in a constitutional crisis and a military intervention by ECOWAS to install the newly-elected president.
"We also wish to express our heartfelt gratitude for the efficiency with which you managed the situation in The Gambia," the bishops wrote. "We congratulate you on the firm position you took … which led to the constitutional transfer of power to the rightfully elected President. With this, you sent a strong and clear signal to all political actors and leaders in our region."
The bishops also noted that The Gambia had been declared an Islamic Republic by Jammeh in December 2015, but that the new president, Adama Barrow, had reversed this: "we are happy that this matter has been reversed with the current leadership," they commented. "We strongly appeal that this situation should not be repeated in any country in our region."
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"Whenever government adopts a particular religion as a state religion, the rights of other citizens to freedom of conscience and worship is infringed upon," the West African bishops wrote.
The bishops also expressed their concern over the herdsmen who have menaced local communities – particularly the Fulani in Nigeria.
"The recurrence of natural and man-made disasters such as floods, storms, desertification, food insecurity, forced migration, and other humanitarian crises related to climate change have become a serious threat to human and animal survival. Of particular concern is the environmental and social havocs wrecked by the herdsmen who move their cattle across communities and national borders in the region," they wrote.
"These herdsmen, often armed with dangerous weapons, are associated with rape, murder, destruction of farms, kidnaping and conflicts. While there is freedom of movement of people and goods in our region, we appeal to our authorities to effectively address this particularly destructive activity."
The bishops concluded by reminding ECOWAS that they are willing to mediate in "governance and political issues" that may arise in the region.
They have created liaison offices with national parliaments, and "monitor public policies and their implementation in order to promote good governance and the common good in public affairs."