Islamic Interpretation of Dreams (Ibn-i Sirin):

(Claw hammer; Mallet; Sledge; Stone hammer) A hammer in a dream represents the one who has the upper hand, advantage, or influence. Holding a hammer in a dream means receiving honor and great benefits.

A hammer in a dream also represents one’s helper and it could mean money for one who uses it to earn a living.

A hammer in a dream also connotes evildoing, or expressing oneself loud with clamor.