Pastor T.D. Jakes Appears to Have Medical Emergency During Sermon

T.D. Jakes -- a popular Christian pastor -- seemed to have a medical emergency during his Sunday sermon ... convulsing onstage.

The preacher and motivational speaker was speaking to his audience both in the church and at home via streaming ... and, while his voice seemed quiet and he wiped sweat from his brow, nothing appeared out of the ordinary at first.

Check out the vid ... Jakes suddenly stops speaking -- letting his hands fall to his sides, and he begins to shake. Several people from backstage rush to his aid, and the stream cuts out.

This comes seconds after Jakes tells his audience he loves them and talks about going to visit someone in the hospital who ends up encouraging the visitor -- almost like he knew something was wrong.

It's unclear what exactly happened to Jakes ... we've reached out to his camp for more details -- so far, no word back.

If you don't know, Jakes ... he's a senior pastor at The Potter's House, a megachurch based in Dallas, Texas. He's written a number of books on religion and self-help.

He rose to national attention last year when rumors about an alleged relationship with Diddy began to surface online ... rumors he shot down fiercely during his Christmas address last year.

Hopefully Jakes is alright and makes a full recovery.