What does it mean to have just one God

Monotheism is the fundamental belief shared by Judaism, Islam, and Christianity. However, the concept of monotheism raises the question of what it entails to have just one God. There appears to be a distinction between the following two statements: * I believe there is just one God * I have just one God (Edit: Better phrasing - what does it mean to actually belong to him, not just to believe him) The first statement, „I believe there is just one God,“ is less demanding. It implies a belief in the existence of a single deity without any specific implications. An individual can hold this belief without acknowledging or engaging with the deity, thereby maintaining the validity of the statement. While such an approach may not be very intelligent (not doing what he says while believing that he exists), it does not contradict the assertion that „I believe there is just one God.“ Conversely, the second statement, „I have just one God,“ carries greater significance and implies practical implications for an individual’s life. Consequently, the question arises: What does this statement actually mean in practical terms? ---------------- Edit: I deleted the Judaism flag. But since, in Dtn. God, asks us not to follow any prophet that leads Israel to other Gods, even if he does perform miracles, a correct christian answer that answers this question should be - at least in my opinion, also be a correct Jewish one. The distinction stems from a point Fr. Mike Schmitz makes in his "The Bible in a year" podcast. He said that it is important for God not merely to believe in him, but actually to belong to him. The latter is what I described using the unfortunate wording "I have only one God". (Context: I am a german native, and "Ich habe nur einen Gott" would mean "I have only one God", but can also mean "I belong to just one God". Nobody here says "Ich gehöre nur einem Gott", thats where the misunderstanding comes from, sorry about that)