Overall meaning : Allah Almighty commands the orphans’ custodians to restore to the orphans under their custody their property when they come of age, and forbids them from exchanging the good of it for the bad one—for instance by taking any part of it and leaving other lawful sources he has provided for them or by substituting worthless things of their own for their valuable ones. He also prohibits them from mixing their own property up with that of the orphans with the intention of unlawfully consuming it and cheating them out of it. Doing do, He warns, is a great sin indeed.
Regarding those guardians who fear they will not be able to observe their rights with exact fairness if they marry the orphan girls in their custody or if they fear they will not be able to honourably discharge their duties towards them, Allah exhorts them to look elsewhere and marry of other women as may be agreeable to them, two, or three or four.  If, however, they fear they cannot maintain equality among them, they should marry one only or just confine themselves to the slave-girls they may own. That is more likely to avoid injustice.
He also orders men to give the women they marry their bridal due (dowry) cheerfully and willingly, considering it a duty; but if their wives give up all, or part of, the dowry to them of their own free will, then they may take it with good feelings and enjoy it as lawfully theirs.
Then He prohibits people from giving their own property—which is a means of their own support—to those who are unable to look after it wisely, and from giving an incompetent person in their custody his property if he does not know how to manage it wisely.  They may, however, use it to satisfy the basic needs of those in their custody, such as food, drink, shelter and clothing, and to speak to them in a kind and amiable manner.
Allah Almighty also instructs the orphans’ guardians to test the orphans in their custody regarding their religion, reasoning and conduct before they attain puberty. If they reach maturity and they find them capable of sound judgement and that they are able to manage their affairs well, then they should hand over to them their property. They should not unnecessarily take anything from their property, nor should they consume it wastefully and hastily before they come of age and claim it. If the guardian is wealthy, he should abstain from taking anything from it altogether by charging a fee for the execution of his functions and be content with what Allah has provided for him. But if he is poor, he may remunerate himself by having a just and reasonable amount that would customarily satisfy the need of a poor person like himself.  When guardians hand over to the orphans in their custody their property, they should call in some witnesses to be present to ensure they have received their property in full and so that they may not deny it; but sufficient is Allah as a reckoner who takes full account of everything people do.