I couldn't understand the case use in Bach's verses

There is a verse in one of Bach's Kantate's

Ich habe den Heiland, das Hoffen der Frommen,
Auf meine begierigen Arme genommen.

I assume, with my A1 German, that den Heiland is accusative case and the nominative version is der Heliand. But when I search the word in google, it says Heiland is die Heiland. What am I missing? Was the language use different in Bach's times?