According to this preaching, God doesn't allow polygamy because God always need is anointed to be a person of one wife. But you see, people do usually choose things for themselves. Like Solomon who had many wives including concubines, that later led him to disobey God and fell from the grace of God.
According to the servant of God, men are given freedom to choose for themselves because God doesn't impose things on people. however, what you do and the decisions you have taken, you will be sure answerable in the day of judgement.
therefore it is important to make right decisions so God should guide our back. If you had missed this teaching, it is recommended that you listen to it carefully. Amen!!