νηστεύωnēsteúō

Same root

• νῆστιςnēstis · G3523not eating, i.e. abstinent from food (religiously)
• νηστείαnēsteía · G3521abstinence (from lack of food, or voluntary and religious); specially, the fast of the Day of Atonement

Where it appears

Appears 20 times in the Bible.

• Matthew 4:2 For forty days and forty nights he fasted and became very hungry.
• Matthew 6:16 “And when you fast, don’t make it obvious, as the hypocrites do, for they try to look miserable and disheveled so people will admire them for their fasting. I tell you the truth, that is the only reward they will ever get.
• Matthew 6:17 But when you fast, comb your hair and wash your face.
• Matthew 6:18 Then no one will notice that you are fasting, except your Father, who knows what you do in private. And your Father, who sees everything, will reward you.
• Matthew 9:14 One day the disciples of John the Baptist came to Jesus and asked him, “Why don’t your disciples fast like we do and the Pharisees do?”
• Matthew 9:15 Jesus replied, “Do wedding guests mourn while celebrating with the groom? Of course not. But someday the groom will be taken away from them, and then they will fast.