Christ is talking about loving others still, and he says that love should be expressed, and it should be expressed in this very practical way. Love is about doing; it is expressed in the way we act towards others.
But perhaps the other will not understand their own needs properly. They will not grasp why we act as we do, and may even misread our actions. Are we to act in the way they expect us to act, so that we have an appearance of doing them good, when in fact we know that there is something else we could do that would be better for them? No we are to act according to the light that we have. We may see their need better than they see it themselves. It may be that what we do for them is not something they would do for themselves, but we are allowed to act according to our superior insight. A parent acts to discipline their child, but the child may not see the wisdom or the kindness in the act of discipline, nevertheless the parent proceeds, and waits for understanding to come later. The doctor prescribes treatment or medicine which the patient finds deeply unpleasant, but it is given for their good.
Our doing costs us something. At the very least it costs us thoughtfulness, but there are situations in which the interests of two individuals compete with each other. It may be that we can only give to the other by going without ourselves. In this case what we do is to some extent an act of self-sacrifice, as well as a kindness to them, but the same rule applies: that we to do to them as we would have them do to us. We are to put them first, and in doing so love has a greater price to pay and consequently is a greater expression of love.
In the example just given of one who takes away our possessions, we are faced with an enemy. Not that we have made them our enemy, but they have made us their enemy. This instruction about what we should do to them applies to enemies just the same. The rule of Christ applies in this case also. Here there is an extra cost, for we have to return good for evil, and this goes against our natural instinct. But we do it because the Lord has commanded us to do it, and this makes it possible for us. If he has told us to act in this way, then that is enough for us, whether we understand it or not. But we do understand it. We are being told to act like our heavenly Father, who gives good gifts to the righteous and the wicked. We lose nothing by imitating our Father in this way, and we gain much, even if we lose this world’s goods.