'Acceptable' in the Bible

Even those I will bring to My holy mountainAnd make them joyful in My house of prayer.Their burnt offerings and their sacrifices will be acceptable on My altar;For My house will be called a house of prayer for all the peoples.”

“Is it a fast like this which I choose, a day for a man to humble himself?Is it for bowing one’s head like a reedAnd for spreading out sackcloth and ashes as a bed?Will you call this a fast, even an acceptable day to the Lord?