1 John

John taught the saints -

"That which we have seen and heard declare we unto you, that ye also may have fellowship with us: and truly our fellowship is with the Father, and with his Son Jesus Christ.
4 And these things write we unto you, that your joy may be full.
5 This then is the message which we have heard of him, and declare unto you, that God is light, and in him is no darkness at all.
6 If we say that we have fellowship with him, and walk in darkness, we lie, and do not the truth:
7 But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin." (New Testament 1 John 1:3 - 7)

John talks of the importance of fellowship with God first, then he follows that as we do, we have fellowship one with another. It seems to follow the great commandments -

"...thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy strength, and with all thy mind; and thy neighbour as thyself." (New Testament Luke 10:27)

In our society today, it is politically correct to love your neighbor, but it is of greater importance to love God first. President Ezra Taft Benson said -

“The world largely ignores the first and great commandment—to love God—but talks a lot about loving their brother. They worship at the altar of man. Would Nephi have slain Laban if he had put the love of neighbor above the love of God? Would Abraham have taken Isaac up for a sacrifice if he had put the second commandment first?

The attitude of the world is reflected in a phrase of falsehood that reads, ‘Presume not God to scan, the proper study of mankind is man.’ But only those who know and love God can best love and serve his children, for only God fully understands his children and knows what is best for their welfare. Therefore, one needs to be in tune with God to best help his children. That’s why the Church, under the inspiration of the Lord, encourages its members to first look to themselves, then their family, then the Church and if need be to other voluntary agencies to help solve the problems of poverty, unemployment, hunger, sickness, and distress. Those who are not moved by that same inspiration turn instead to government. Such man-made course of action does little good compared to the Lord’s approach and often results in doing great harm to our Father’s children, even though the intentions may seem to have been noble.

Therefore, if you desire to help your fellowmen the most, then you must put the first commandment first.

When we fail to put the love of God first, we are easily deceived by crafty men who profess a great love of humanity, while advocating programs that are not of the Lord.” (Ezra Taft Benson in CR, Oct. 1967, p. 35.)

We see this as John teaches -

"...he is the propitiation for our sins: and not for ours only, but also for the sins of the whole world.
3 And hereby we do know that we know him, if we keep his commandments." (New Testament 1 John 2:2 - 3)

For -

"..whoso keepeth his word, in him verily is the love of God perfected: hereby know we that we are in him.
6 He that saith he abideth in him ought himself also so to walk, even as he walked." (New Testament 1 John 2:5 - 6)

And of those that say -

"...I know him, and keepeth not his commandments, is a liar, and the truth is not in him." (New Testament 1 John 2:4)

Therefore -

"...abide in him; that, when he shall appear, we may have confidence, and not be ashamed before him at his coming.
29 If ye know that he is righteous, ye know that every one that doeth righteousness is born of him." (New Testament 1 John 2:28 - 29)

So we must first love God and then we must love our fellowman for -

"If a man say, I love God, and hateth his brother, he is a liar: for he that loveth not his brother whom he hath seen, how can he love God whom he hath not seen?" (New Testament 1 John 4:20)

"Herein is love, not that we loved God, but that he loved us, and sent his Son to be the propitiation for our sins.
11 Beloved, if God so loved us, we ought also to love one another....If we love one another, God dwelleth in us, and his love is perfected in us." (New Testament 1 John 4:10 - 12)

Because -

"Hereby know we that we dwell in him, and he in us, because he hath given us of his Spirit."
(New Testament 1 John 4:13)