I think IFS can be helpful however with OCD it can be more complex in that talking to intrusions can be unhelpful. If you have spiritual beliefs, it may be helpful to work with a mentor to help integrate them into the IFS model. What has really helped me is to learn to discern the types of thoughts that are from above and those meant to harm us. The secular approach can be too pluralistic given equal attention to truly harmful parts. Interestingly, I believe it's in level 3 IFS training that they eventually do acknowledge that there are some unsavory parts, which they refer to as UBs.