Jesus schläft, was soll ich hoffen?, BWV 81, is a church cantata by Johann Sebastian Bach. He composed it in 1724 in Leipzig for the fourth Sunday after Epiphany and first performed it on 30 January 1724.

The cantatas composed by Johann Sebastian Bach, known as Bach cantatas, are a body of work consisting of over 200 surviving independent works, and at least several dozen that are considered lost. As far as known, Bach's earliest cantatas date from 1707, the year he moved to Mühlhausen, although he may have begun composing them at his previous post in Arnstadt. Most of Bach's church cantatas date from his first years as Thomaskantor and director of church music in Leipzig, a position which he took up in 1723.