Jesus said unto him, Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind. This is the first and great commandment. And the second is like unto it, Thou shalt love thy neighbour as thyself. On these two commandments hang all the law and the prophets.
The first commandment is very great and the second is reciprocal to the first. In loving God with all thy heart, and with all thy soul, and with all thy mind a person will naturally love his neighbor; therefore, such love will also be imparted to his family, his country, and the world.
The New Covenant commandments (there are only two) of love are superior to the Old Covenant commandments. They are positive, whereas the law was negative. In the New Covenant, the commandments of love are superior because they are complete by the finished work of Jesus Christ. They are superior because they begin at the heart and lead us directly to our need for the Holy Spirit to guide us in our Christian walk.
We must not love God only with the heart, but with the whole heart. The whole heart is opposed either to a divided and detached heart or to an inconsistent and an inactive heart. The whole heart is focused on the loving and pleasing God. It is our indispensable duty to love God. To love God is our great natural duty. Man would more naturally love God than himself, were it not for sin.
Loving God with our whole heart is impeded by self-love, love of the world, spiritual apathy and carelessness of spirit, the love of sinful behaviors whatsoever or a disproportionate love of things which are lawful.
The great guiding influence of the Christian life is to be our love for God and others. Unfortunately, Christians often spend so much time in following the traditions of men, man-made standards and religious rituals that they have little, or no, time to attend to anything else. There are only two requirements: love God with all thy heart, and with all thy soul, and with all thy mind and love thy neighbor as thyself. If you take care of that, everything else will take care of itself.