Power and ideology, which are two main concerns in critical discourse analysis (CDA) approach, have become medium for each other to innervate and sustain each other in the society. Both of them can be manifested via the use of some linguistic expressions and forms. Halliday’s Systematic functional linguistic (SFL), can be applied in the sake of investigating those linguistic forms in harmony with CDA. The current article investigates the use of deixis to represent power relations and ideologies in two messages of Abu Bakr Al-Baghdadi (leader of ISIS). The analysis involves CDA based on the works of van Dijk (2000 & 2008) and Fairclough (1989, 1995& 2003) in addition to Halliday’s SFL (1985 & 1994). The conclusions manifested different power relations in Al-Baghdadi messages (Allah Almighty and Al-Baghdadi, Al-Baghdadi and Non-Muslims, and Al-Baghdadi and the Muslims). Further, ideologies of principle belief, the believers’ duty and political ideologies are all identified through the use of personal deixis such the pronoun ‘I’ and the pronoun ‘we’ refer to Al-Baghdadi (the speaker) and to ISIS (his group) respectively, the pronoun ‘Him’ and the pronoun ‘He’ represent Allah Almighty. In this context, the pronoun ‘we’ has no power over anyone, while the pronoun ‘Him’ is the powerful one.