Islam and Christianity "clearly do not worship the same God", according to leading preacher and evangelist Rev Franklin Graham.

Graham criticised the proposal at Wheaton College in Illinois to end their plans to fire a professor who said she believed Muslims and Christians worship the same God.

On Facebook he wrote: "Both my father Billy Graham and my mother attended Wheaton College in Illinois – in fact that's where they met. I'm surprised and disappointed that the faculty council there is now recommending the college drop their plans to terminate a professor who published that she believed Islam and Christianity worship the same God in December.

"This is no minor issue that should be debated. Islam denies that God has a Son. They deny that Jesus is God. They do not believe in a Triune God – the Father, the Son, and the Holy Spirit. I can tell you – Islam and Christianity clearly do not worship the same God. How the faculty council can now support this professor being allowed to teach students is deeply concerning."

His outrage follows the controversy at Wheaton where associate professor Larycia Hawkins started to wear a headscarf to show solidarity with Muslims. Stanton Jones, provost of Wheaton, which is a well-known private evangelical Christian college, placed her on notice that "termination-for-cause" proceedings would be begun against her.

However, the faculty council has now recommended that the college end its efforts to terminate her contract. In a letter to colleagues, council chairman Lynn Cohick said it should be "withdrawn due to grave concerns about the process."

Earlier, Hawkins defended herself on social media, including on Facebook. 

She said that since she started wearing the headscarf in solidarity with Muslim women, she had experienced "pushback" almost exclusively from other Christians.

"The pushback has primarily centered on the claim that Christians and Muslims worship the same God," she wrote.

She argued that asserting religious solidarity with Muslims and Jews "will go a long way toward quelling religious violence and enervating religionist fear of the religious other."

She added that her position was one held for centuries to be valid by countless Christians, such as church fathers, saints, and "regular Christian folk like me".

Calling for peaceful disagreement on theological points such as views on the Triune God, the Creed and the Virgin Birth, she pleaded: "Let there be unity in our diversity of views about all of the above. My wearing of the hijab as an act of advent devotion has certainly caused some to question the sincerity of my devotion. To those who question the authenticity of my faith, I love you."

As well as writing on Facebook, Franklin Graham published five successive tweets on Twitter, all of which were "liked" and retweeted many hundreds of times:

In its statement of faith, Wheaton College says: "WE BELIEVE in one sovereign God, eternally existing in three persons: the everlasting Father, His only begotten Son, Jesus Christ our Lord, and the Holy Spirit, the giver of life; and we believe that God created the Heavens and the earth out of nothing by His spoken word, and for His own glory."

The statement continues: "WE BELIEVE in the existence of Satan, sin, and evil powers, and that all these have been defeated by God in the cross of Christ.

"WE BELIEVE that the Lord Jesus Christ died for our sins, according to the Scriptures, as a representative and substitutionary sacrifice, triumphing over all evil; and that all who believe in Him are justified by His shed blood and forgiven of all their sins.

"WE BELIEVE that all who receive the Lord Jesus Christ by faith are born again of the Holy Spirit and thereby become children of God and are enabled to offer spiritual worship acceptable to God."