Can I take 403b 9 distributions as nontaxable for housing? I am 63 and served as a pastor for 25 years. I no longer hold ministerial credentials.

See if this article answers your questions. 

https://pensionfund.org/uploads/Housing-Allowance-Information-for-Retired-Ministers.pdf

I would start with these guides as well.

https://www.ecfa.org/FileAccess.aspx?file=2020MinTaxes&source=NPO

One interesting question is why you no longer hold credentials.  You must be a "retired minister" to use the exclusion on your pension or annuity.  Depending on how, when and why you lost your credentials, you might not be a "retired minister" as defined by your denomination. That is something you would have to review with your church.  I don't see any specific rules in the IRS documents that discuss this situation, they just say "retired minister."

Also, it's important to be aware that the tax-free housing allowance treatment is only allowed if your retirement account is sponsored by your church or denomination.  If you were to do a rollover to a personal IRA (for example), then your withdrawals would not qualify even if you are considered a retired minister.