Question: After You resurrected, why did You stay for 40 days?
God’s answer:
Meaning: According to the law, as given by God to the Israelites, when a woman bears a son, she goes through a 40 day purification period, during which she cannot touch anything that is hallowed. After 40 days, she then goes to the temple and offers a lamb or two turtledoves/pigeons. This is what the Presentation of Jesus was.
When Jesus rose from the dead, He returned to a new life (victory over death). God, who is Jesus, is then like a mother who has brought forth a new life to the world (a son). So, like a mother who goes through 40-day purification, God, who is Jesus, also had to go through the purification period. After which, He offered a lamb - Himself, during the ascension
The number forty (40), it would seem, is the number for purification (forty days of flood, forty days in the desert (Israelites). Forty days of fasting by Jesus, forty days when Moses went to the mountain and 40 days of purification for mothers who bear a son.