Alma 41:11 - 41:15
Alma 41: 11 And now, my son, all men that are in a state of nature, or I would say, in a carnal state, are in the gall of bitterness and in the bonds of iniquity; they are without God in the world, and they have gone contrary to the nature of God; therefore, they are in a state contrary to the nature of happiness.
The condition of men and women in mortality is one of being in a state where we do not have God in our immediate presence. In fact, we are living in a world where evil is rampant and one is so easily caught up in temptation and sin. Because of our condition, we are living such that true happiness is very difficult for us all to acquire on account of the nature of the mortal man.
Alma 41: 12 And now behold, is the meaning of the word restoration to take a thing of a natural state and place it in an unnatural state, or to place it in a state opposite to its nature?
So the meaning of the word restoration is not to restore something from one state to another state that is opposite of its actual nature or disposition.
Alma 41: 13 O, my son, this is not the case; but the meaning of the word restoration is to bring back again evil for evil, or carnal for carnal, or devilish for devilish—good for that which is good; righteous for that which is righteous; just for that which is just; merciful for that which is merciful.
The meaning of restoration as defined by the gospel is to give to the mortals the same state they chose in mortality whether it was righteousness or evil in the next life. It is to restore to them after the resurrection what they wanted in this life for the eternities because they were restricted because of being a spirit.
Alma 41: 14 Therefore, my son, see that you are merciful unto your brethren; deal justly, judge righteously, and do good continually; and if ye do all these things then shall ye receive your reward; yea, ye shall have mercy restored unto you again; ye shall have justice restored unto you again; ye shall have a righteous judgment restored unto you again; and ye shall have good rewarded unto you again.
So it is imperative that one deals righteously with their fellow men. If your conduct is loving, kind, and honest you will be restored to the condition in the next world to be able to continue to do so. if you are merciful and loving towards all men, you will be restored to the condition where God and others will be the same to you as well.
Obviously the same is true if you were unmerciful and unkind towards others. That will be your fate in the next world after your resurrection. That does not sound like a place I want to be.
Alma 41: 15 For that which ye do send out shall return unto you again, and be restored; therefore, the word restoration more fully condemneth the sinner, and justifieth him not at all.
The basic concept is that how you treat others will come back to you and you will be treated in like manner. So how we find ourselves being treated by others is a measure on how we treated others. This is a fool proof way to see if we are a righteous person, by measuring how we are treated by others in general.
The saying “what goes around, comes around” is the basic concept here.