'Unspeakable' in the Bible

In the same way the Spirit [comes to us and] helps us in our weakness. We do not know what prayer to offer or how to offer it as we should, but the Spirit Himself [knows our need and at the right time] intercedes on our behalf with sighs and groanings too deep for words.

Now to Him who is able to keep you from stumbling or falling into sin, and to present you unblemished [blameless and faultless] in the presence of His glory with triumphant joy and unspeakable delight,