'Months' in the Bible

At which time Moses came to birth, and he was very beautiful; and he was kept for three months in his father's house:

And he was there for a year and six months, teaching the word of God among them.

And he went into the Synagogue, and for three months he was preaching there without fear, reasoning and teaching about the kingdom of God.

And when he had been there three months, because the Jews had made a secret design against him when he was about to take ship for Syria, he made a decision to go back through Macedonia.

And after three months we went to sea in a ship of Alexandria sailing under the sign of the Dioscuri, which had been at the island for the winter.