No one lights a candle or turns on the electric light when a beam of sunshine is streaming in full blaze through your window. You will not be satisfied with the flicker of the candle when you can so easily, have the brilliance of the lamp that God has set up in the heavens.
Before the Holy Spirit descended upon them, the first apostles guided themselves in many things by the uncertain glimmer of human reason; after Pentecost the divine light shone in their minds and in the clarity it gave them, they seemed to themselves to have been hitherto blind and groping.
There is a way of seeing divine truth that is narrow and restricted. He who walks in this way will do a certain amount of work for God, but he will be exceedingly careful not to do too much; he will measure accurately where his obligations begin and end; he will show himself reluctant to take on anything extra, especially if it encroach on what he had planned was to be his time off. He will sometimes carry off a brilliant achievement, but only if it bring with it the popularis aura. He will easily tire of effort if it must be made on behalf of some task the value of which is known only to God.
If you are willing to swing the censer before him and keep praising him, you will manage to get a fair amount done. If he is voted a success, he will be egged on to try again. Human respect will often deter him; natural ennui will soon slow him down; if opposition comes, he will fail to stand up to it. In a word, he is motivated, very largely, by selfishness. He never altogether loses sight of the advantages and disadvantages that will accrue to self. He is of the earth, earthly, and even the works he undertakes ostensibly for God are crippled and seriously vitiated.
He walks through life with only the weak light of the candle to direct his steps. There is much more he could do and ought to do, but he does not see it. There is a flaw in his approach to God and the interests of God, but he cannot detect it. He may be a faithful enough servant, but he is far from being a loving child of the heavenly Father.
Before the descent of the Holy Ghost, the first apostles were to some extent men of this type. They had run away when danger appeared to the Master; they dreamed, even after the Resurrection, of a mere temporal kingdom of Israel; they were "foolish and slow of heart" even when the risen Christ was walking by their side. They did not possess the divine light of discernment. They were cramped in their outlook, their horizon was small, they failed to appreciate the plans and the views of Our Lord, Who had come to sweep the world, to begin and carry through a revolution that would be coterminous with the universe.
"If," says Thomas a Kempis, "thou reliest more on thy reason than on the virtue that subjects to Jesus Christ, thou wilt seldom or hardly become an enlightened man. For God will have us wholly subject to Him, and to transcend all reason by an inflamed love."
This was the first wonderful change wrought in the apostles as soon as ever the Spirit of God came down upon them. He came under the form of tongues of fire, signifying light and heat. The whole orientation of their minds towards the things of God underwent a profound transformation.