No, they don't. That's the lie being sold. Nothing in the relevant section of 6103 requires any such thing.
(1)Committee on Ways and Means, Committee on Finance, and Joint Committee on Taxation
Upon written request from the chairman of the Committee on Ways and Means of the House of Representatives, the chairman of the Committee on Finance of the Senate, or the chairman of the Joint Committee on Taxation,
the Secretary shall furnish such committee with any return or return information specified in such request, except that any
return or
return information which can be associated with, or otherwise identify, directly or indirectly, a particular
taxpayer shall be furnished to such committee only when sitting in closed executive session unless such
taxpayer otherwise consents in writing to such
disclosure.
That is the law and good luck finding "legislative purpose". Oversight, upon which this law is based, does not require legislation. It is also not the right of an inferior to tell a branch of government that he or she will tell them that they cannot act upon the law or exercise their rights.
Congress has to justify nothing. It is up to anyone else to convince the SCOTUS that House cannot follow the law, and good luck with that.