There seems to be an observable transformation in Peter having the Spirit now. We have not heard Him quote and reason Old Testament scripture before let alone so boldly with such confidence. Just days ago he was part of a group that was over extending itself beyond the direction of the Spirit, but now he seems fully in step and infused by It. The Spirit is bringing Jesus' words and teachings to effect and Peter and the group are an observable example.
The spectacle of the manifestation of the Spirit is providing the opportunity, the revelations (past/present/future) by the Spirit is providing the conviction, the unity in the Spirit is providing the furtherance and continuance. The very presence of the Spirit in this manner is the absolute proof.
2012 - pBiblx2 Field Wise Bible System Version 2.0.9d - GPL3