True Christianity, Christianity centered around and built on the message and character of Jesus, cannot be an ideology in the classical sense of the word. “Christian ideology” is an oxymoron (unless one merely means by “ideology” any system of belief which then sort of makes it a useless term).
True, authentic, Jesus-centered Christianity is anti-ideological belief system. Of course, many so-called “Christians” throughout history have attempted to make their “Christianity” into an ideology. They still do it. In my opinion, however, that attempt, however successful or unsuccessful, reveals the inauthenticity of their “Christianity.”
Yes, of course…true, authentic Christianity includes belief in something called the “kingdom of God” which sounds to many people, including many Christians, like an ideology. It isn’t; it is a Christ-centered vision of a social order without mastery-over. It is not, as with all ideologies, a humanly contrived socio-political solution to all human problems to be imposed politically. Its “heartbeat” is, as Pope Francis says, mercy. If true, authentic Christianity is an “ideology,” it is an anti-ideological ideology. All true ideology is idolatry from a Christian perspective and that is exactly why true, authentic Christianity must exclude and resist all ideologies.