Is the husband obligated to give his first wife the same amount of money that he gave to his second wife?

The jurists differed on the obligation of justice between wives concerning what exceeds the obligatory maintenance. The majority of them hold that it is not obligatory, arguing that equality in everything is difficult, and that what is obligatory is justice in division and overnight stays. However, others held that justice is obligatory in everything possible, including gifts, and this is the preferred opinion chosen by a number of contemporary scholars, based on the saying of the Prophet, peace and blessings be upon him: "Whoever has two wives and inclines to one of them, will come on the Day of Resurrection with his side leaning." The standard here is that the husband must be just between his wives in giving gifts, unless one of them waives her right willingly.