The third and final item in the list of three things that abide, given by Paul in 1 Corinthians 13:13, is love. And now abide faith, hope, love, these three; but the greatest of these is love. You may note that Paul additionally asserts that the greatest is love.
The context of Pauls statement is a chapter where love is defined through personification. Love suffers long and is kind; love does not envy; love does not parade itself, is not puffed up; does not behave rudely, does not seek its own, is not provoked, thinks no evil; does not rejoice in iniquity, but rejoices in the truth; bears all things, believes all things, hopes all things, endures all things. Love never fails (1 Corinthians 13:4-8).
Such love is stated by Paul to be necessary to be acceptable to God. Though I speak with the tongues of men and of angels, but have not love, I have become sounding brass or a clanging cymbal. And though I have the gift of prophecy, and understand all mysteries and all knowledge, and though I have all faith, so that I could remove mountains, but have not love, I am nothing. And though I bestow all my goods to feed the poor, and though I give my body to be burned, but have not love, it profits me nothing (1 Corinthians 13:1-3).
The apostle John agrees with Paul, and stated such in his first epistle, We know that we have passed from death to life, because we love the brethren. He who does not love his brother abides in death (1 John 3:14). From these passages it becomes obvious that love holds a place of great importance in the life of anyone who professes to be a child of God.
The greatness of love can be seen in its definition. The Greek language had several words which are translated love our English Bibles. The word we are concerned with derives from the Greek agape. It has been defined simply as actively seeking the welfare of others. As W.E. Vine put it, Christian love, whether exercised toward the brethren, or toward men generally, is not an impulse from the feelings, it does not always run with the natural inclinations, nor does it spend itself only upon those for whom some affinity is discovered. Love seeks the welfare of all,... (Vol. 2, pge. 21).
The greatness of love can be seen in Gods expression of love for man. Again, Vine wrote, Love can be known only from the actions it prompts. Gods love is seen in the gift of His Son (ibid). As John wrote, In this the love of God was manifested toward us, that God has sent His only begotten Son into the world, that we might live through Him. In this is love, not that we loved God, but that He loved us and sent His Son to be the propitiation for our sins (1 John 4:9-10).
An interesting point that Vine makes is that love does not always run with natural inclinations, nor does is spend itself only upon those for whom some affinity is discovered. This is amply demonstrated in God sending his Son to a rebellious world. For when we were still without strength, in due time Christ died for the ungodly. For scarcely for a righteous man will one die; yet perhaps for a good man someone would even dare to die. But God demonstrates His own love toward us, in that while we were still sinners, Christ died for us (Romans 5:6-8).
This willingness of God to sacrifice His only Son for mankind, despite the rebellious nature of men, speaks to Gods nature and character. He did not do it because of anything man did to make it a desirable action. God did it because of the type of being He is. He who does not love does not know God, for God is love (1 John 4:8).
Love is the foundation of all that is Christian. It is the reason for our hope of redemption, (For God so loved the world that he gave his only begotten son... John 3:16); It is the reason we serve God, (If you love me, keep my commandments. John 14:15); It is what motivates us to preach the gospel to the lost, (I am a debtor both to the Greeks and the barbarians, both to the wise and the unwise. So, as much as is in me, I am ready to preach the gospel... Romans 1:14-15); It is the foundation for our relationship as brethren in Christ, (And this commandment we have from Him: that he who loves God must love his brother also. 1 John 4:21).
When all is considered, truly, the greatest of these is love (cf. 1 Corinthians 13:13).