The money coming from Lewandowski could be important for Barcelona. I don't think there is a team in the world that doesn't know that Barcelona is in a difficult period economically. Lewandowski could be an important source of prestige in Saudi Arabia. If Lewandowski wants to earn good money before he retires, he can go to Saudi Arabia. I'm sure he will be successful while he plays in Saudi Arabia because he is still very good and in great shape at this age.
Robert Lewandowski might move to Saudi Arabia and this could greatly help Barcelona with their money problems. Money from this transfer would definitely help Barcelona financial situation. Also Lewandowski choice to play in Saudi league might be smart one considering how old he is and his desire to get good contract before he stops playing. He will likely do very well in Saudi Arabia because he is extremely skilled player and is in great physical shape. In general this move would be good for both Lewandowski and Barcelona and would be beneficial for everyone involved.