This unity is only possible "in love." It is the love of God _to_ us that unites us to Him, and it will be the love of God _in_ us that unites us to our brethren. There is no power like love to bind Christians together. We may not see eye to eye on all aspects of truth; we may not all use the same methods of worship and service, but if we love one another God dwells in us and among us, and adds His own seal of blessing to the work done for Him. Let every Christian be fully assured that in so far as he is striving, praying, and labouring for the union of God's people in love, he will be doing one of the most powerful and blessed pieces of work for his Master, and one of the greatest possible pieces of disservice to the kingdom of Satan. Contrariwise, the Christian man or Christian Church that stands out for separateness and exclusiveness is one of the best allies of Satan, and one of the most effective workers for the kingdom of darkness. He asked for spiritual _certitude_: "Unto all riches of the full assurance of understanding." Wealth is a favourite metaphor of St. Paul, and is used to denote the fulness and abundance of the Christian life as conceived by him. Mark how he piles phrase upon phrase--"understanding," "fulness of understanding," and then "wealth of fulness of understanding." To the Apostle, the mind was one of the essential powers and principles of the Christian life. So far from thinking according to a modern fashion that the less one uses the mind the better Christian one is, St. Paul, following his Master, ever emphasised the duty and glory of loving God "with all the mind." This wealth of the fulness of "understanding" means an abundance of conviction, both intellectual and moral, that Christianity is what it claims to be, and that the Christian life is the perfect satisfaction of all the different parts of man's nature. He prays that they may "rise to the whole wealth of the full exercise of their intelligence" (Moule). Just as we find elsewhere "the fulness of faith" (Heb. x. 22), "the fulness of hope" (Heb. vi. 11), and "much fulness" (1 Thess. i. 5), so here the Apostle desires them to enjoy to the full the intelligent grasping of assurance of Christian truth which was theirs in Christ. In the same spirit Luke writes to Theophilus: "That thou mightest know the certainty of those things wherein thou hast been instructed." A firm conviction of the understanding is one of the greatest needs, as it is also one of the greatest blessings, of the Christian life. If a Christian cannot say, "I know," "I am persuaded," he is lacking in one of the prime essentials of a vigorous experience. Let us ponder, then, this remarkable phrase, "the whole wealth of the fulness of intelligence," and see in it one of the absolute necessities of daily experience.