In a statement signed by his Chief Press Secretary, Mr. Paul Mumeh, Mark said besides banning same sex marriage, the act also makes homosexuality a criminal offence punishable by imprisonment of not less than 14 years.
The Senate President made the disclosure while addressing the Catholic faithful and guests at the civic reception in honour of the Cardinal John Onaiyean in Abuja.
He said: "We will not compromise on this. I want to invite you all to join the crusade of decency in our society. There are many good values we can copy from other societies but certainly not this one (same sex marriage).
"We have to prove to the rest of the world, who are advocates of this unnatural way that we Nigerians promote and respect sanity, morality and humanity. Every individual is a product of the union of a man and woman."
He acknowledged the cordial relationship between the Nigerian state and the Church, and pledged that the National Assembly would continue to do all within the law to ensure religious freedom and peaceful co-existence in the country.
Mark added that the National Assembly would continue to support religious programmes that have positive bearing on Nigerians but was quick to condemn in the strongest possible terms religious intolerance or extremism.
He therefore enjoined spiritual leaders to continue to pray for good governance, peace and security which are major challenges in our society today.
In a remark, Cardinal Onaiyekan expressed appreciation to the Pope Benedict XII, the government and people of Nigeria for their prayers and support especially since his elevation to the Collage of Cardinals, saying he will continue to be a crusader for peace and unity of the nation where every citizen have a sense of belonging.
Earlier, the chairman of the reception organising committee, Rev. Father Innocent Jooji, noted that Onaiyekan a worthy soldier of Christ has brought honour to the nation with his elevation to the College of Cardinals.
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