Who was the first to formulate the doctrine of the Trinity in Christianity? And when did it emerge?

The first to distort the religion of the Christians was Paul. Sheikh Rahmatullah al-Hindi mentioned that Paul was the first to call for the doctrine of the Trinity, citing Paul's saying: "The grace of our Lord Jesus Christ, and the love of God, and the communion of the Holy Spirit be with you all," even though Jesus, peace be upon him, called for monotheism and did not speak of the Trinity.