evangelize

To tell people about (a particular branch of) Christianity, especially in order to convert them; to preach the gospel to.

his Apoſtles, whom he ſends To evangelize the Nations

To preach any ideology to those who have not yet been converted to it.

[…] nor is it the task of the Muslim to "evangelize" the unbelieving world.

To be enthusiastic about something, and to attempt to share that enthusiasm with others; to promote.