Zephaniah reads the letter to Jeremiah (Jer 29:29-29:29)

“The priest Zephaniah

Read this letter

In the hearing

Of the prophet Jeremiah.”

If Shemaiah was expecting something bad to happen to Jeremiah, he would have been surprised when the priest Zephaniah read his letter to Jeremiah himself. This is not going to work out well for Shemaiah.