It is not necessary to lower Jesus to proclaim Baha'u'llah.

We must welcome the Truth of God wherever we behold it.

The essence of the question is that all these great Messengers came to raise the Divine Standard of Perfections.

All of them shine as orbs in the same heaven of the Divine Will.

All of them give Light to the world.
The task is God's, and God calls not only the Prophets but all mankind to be His co-workers in this creative process.