"Charity or Non-Ulteriority in Christianity and Islam"

This is the foremost thing that God wants people of all religions to know:

"The delight of doing good for its own sake and not for an ulterior motivation is the reward which lasts forever" (Arcana Coelestia 9984).

On Exodus 22:25:

"That this signifies that this must be done from charity, is evident from the signification of “a usurer,” as being one who does what is good for the sake of self-advantage; for a usurer intrusts money to another for the sake of usury, and assists another for the sake of recompense. And because genuine charity does not regard profit or recompense as the end, but the good of the neighbor, therefore by “thou shalt not be as a usurer” is signified that it must be done from charity. 

He who does not know what Christian charity is, may believe that it consists not only in giving to the needy and the poor, but also in doing good to a fellow citizen, to our country, and to the church, for any cause whatever, or for any end whatever. But be it known that it is the end that determines the quality of all a man’s deeds. If his end or intention is to do good for the sake of reputation, or to acquire honors or profit, then the good which he does is not good, because it is done for the sake of himself, and thus also from himself. 

But if his end is to do good for the sake of a fellow citizen, his country, or the church, thus for the sake of the neighbor, then the good which the man does is good, for it is done for the sake of good itself, which, in general, is the neighbor itself (n. 5025, 6706, 6711, 6712, 8123); thus also it is done for the sake of the Lord, for such good is not from man, but from the Lord, and that which is from the Lord is the Lord’s. It is this good which is meant by the Lord in Matthew:

As much as ye did to one of the least of these My brethren, ye did to Me (Matthew 25:40)" (Arcana Coelestia 9210).

We see the command to have non-ulterior love, charity, outright stated in the Sermon on the Mount: 

"But love ye your enemies, and do good, and lend, hoping for nothing again; and your reward shall be great, and ye shall be the children of the Highest: for he is kind unto the unthankful and to the evil" (Luke 6:35).

We also see many references to how people are not to engage in usury, not to follow after a reward, and not to love gifts in the Word; for to charge usury, follow after a reward or love gifts are symbolic of expecting something in return for the good one does rather than first and foremost loving to do good to and to nurture the neighbor.

Usury represents the absence of charity and the presence of ulterior motivation because ulteriority 'charges interest' on good deeds that one does; in the expectation of receiving something in return.

And this is how Jesus Christ explained this same expectation to Muslims:

"2:275: Those who consume interest cannot stand on the Day of Resurrection except as one who is being beaten by Satan into insanity. They say, “Trade is just like interest,” but Allah has permitted trade and forbidden interest. Whoever desists after admonition may keep what is past, but whoever returns is among the companions of the Fire.

2:276: Allah destroys interest and increases charity. He does not like every sinning disbeliever.

2:278–280: O you who have believed, fear Allah and abandon what remains of interest if you are believers. If you do not, then war from Allah and His Messenger is announced. If you repent, you will have your principal, neither harming nor being harmed. If the debtor is in hardship, grant respite until ease; remitting as charity is better for you" (Surah Al‑Baqarah (2:275–281)).