Why was the period of breastfeeding specified as two full years?

The interpretation of verse 233 of Surat Al-Baqarah includes that mothers should suckle their children for two full years for those who wish to complete the suckling, and fathers are responsible for the food and clothing of the nursing mothers according to what is reasonable. Neither parent should use the infant as a means of harm. If the parents agree to wean the infant before the two years, there is no blame upon them, provided there is mutual consent and consultation. The majority of scholars hold that the two years are the maximum period for suckling to be considered legally valid.