ROBERTO - I was born and raised catholic and converted to mormonism a couple of years ago. Even though I'm a mormon now, it dissapoints me greatly that our church that claims to have another testament of jesus christ is more than sixty times smaller than the largest christian church(The Roman Catholic Church) in the world. It disturbs me that catholicisms strength doesn't seem to be fading even with problems it has run into such as catholic priests harming kids and the Protestant reformation. Why would God give the catholic church a more than 1000 year head start to grow more than the mormon church if it isn't his church. I'm really torn between these two churches. They are the only ones that seem to me to have divine authority from god.

JOEL - In one sense you are right, in that, logically speaking, either the Catholic church is true because they trace their authority all the way back to the Apostle Peter, or the LDS Church is true because Joseph Smith received the devine authority from the Apostle Peter, who appeared as a messenger from God.
The key issue is in understanding that God's authority was lost in the years following the establishment of Christ's church through His Apostles.
There are scriptures that emphasize the importance of the presence of Apostles and Prophets holding authority from Christ to establish and maintain His gospel and Church on the earth.

"Ye have not chosen me, but I have chosen you, and ordained you, that ye should go and bring forth fruit, and that your fruit should remain: that whatsoever ye shall ask of the Father in my name, he may give it you." (John 15: 16)

Speaking to the Church Paul said:

"Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God;
And are built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief corner stone;
In whom all the building fitly framed together groweth unto an holy temple in the Lord:
In whom ye also are builded together for an habitation of God through the Spirit." (Eph 2: 19-22)

If you think about what would happen to a building if the foundation was suddenly taken away, you can understand what happened to the Church once the Apostles(the foundation) had died without being replaced. Without their leadership and authority the church fell into apostasy with many false doctrines and practices creeping in.
The scriptures prophesied that there would be an apostasy.

"Behold, the days come, saith the Lord God, that I will send a famine in the land, not a famine of bread, nor a thirst for water, but of hearing the words of the Lord:
And they shall wander from sea to sea, and from the north even to the east, they shall arun to and fro to seek the word of the Lord, and shall not find it." (Amos 8:11-12)

"The earth mourneth and fadeth away, the world languisheth and fadeth away, the haughty people of the earth do languish.
The earth also is defiled under the inhabitants thereof; because they have transgressed the laws, changed the ordinance, broken the everlasting covenant." (Isa 24: 4-5)

Paul spoke of a falling away before the second coming of Christ:

"Now we beseech you, brethren, by the coming of our Lord Jesus Christ, and by our gathering together unto him,
That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand.
Let no man deceive you by any means: for that day shall not come, except there come a falling away first, and that man of sin be revealed, the son of perdition;" (2 thes 2:1-3)

“Now the Spirit speaketh expressly, that in the latter times some shall depart from the faith, giving heed to seducing spirits, and doctrines of devils.” (1 Tim. 4:1)

And from Peter:

"But there were false prophets also among the people, even as there shall be false teachers among you, who privily shall bring in damnable heresies, even denying the Lord that bought them, and bring upon themselves swift destruction.
And many shall follow their pernicious ways; by reason of whom the way of truth shall be evil spoken of." (2 Pet. 2:1–2)

And from the Savior Himself:

"Then shall they deliver you up to be afflicted, and shall kill you: and ye shall be hated of all nations for my name’s sake.
And then shall many be offended, and shall betray one another, and shall hate one another.
And many false prophets shall rise, and shall deceive many.
And because iniquity shall abound, the love of many shall wax cold.
For there shall arise false Christs, and false prophets, and shall shew great signs and wonders; insomuch that, if it were possible, they shall deceive the very elect." (Matt 24:9-12, 24)

The apostasy was prophesied to happen and it did happen. But the scriptures also prophesied about an eventual restoration of the gospel:

"Repent ye therefore, and be converted, that your sins may be blotted out, when the times of refreshing shall come from the presence of the Lord;
And he shall send Jesus Christ, which before was preached unto you:
Whom the heaven must receive until the times of restitution of all things, which God hath spoken by the mouth of all his holy prophets since the world began." (Acts 3:19-21)

The restitution of all things began with the prophet Joseph Smith.
As Jesus said in the Scripture above the apostles were to go out and bring forth fruit(John 15:16); which they did at first, but unfortunately their fruit did not remain after they died.
In order to tell if we truly once again have that correct foundation of Apostle and Prophets we must consider the fruit they bring forth.

"Beware of false prophets, which come to you in sheep’s clothing, but inwardly they are ravening wolves.
Ye shall know them by their fruits." (Matt 7:15-16)

The fruits brought forth by the Catholic Church and others throughout history were the following;

1. The corrupting of the simple doctrines of the gospel of Christ by admixture with so-called philosophic systems.
2. Unauthorized additions to the prescribed rites of the Church and the introduction of vital alterations in essential ordinances.
3. Unauthorized changes in Church organization and government.

The fruits brought forth by Joseph Smith were the following:

1. The restoration of all doctrines established by Christ while He was on the earth.
2. The restoration of the priesthood and with it the proper authorization and performance of ordinances and rites of salvation.
3. Direct communication from God to His prophets:
"Surely the Lord God will do nothing, but he revealeth his secret unto his servants the prophets." (Amos 3:7)
4. The same organization and church government as described in the scriptures below:

"And God hath set some in the church, first apostles, secondarily prophets, thirdly teachers, after that miracles, then gifts of healings, helps, governments, diversities of tongues." (1 Cor. 12: 28)

"Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God;
And are built upon the foundation of the apostles and prophets, Jesus Christ himself being the chief ccorner stone;
In whom all the building fitly framed together groweth unto an holy temple in the Lord:" (Eph 2:19-21)

"And he gave some, apostles; and some, prophets; and some, evangelists; and some, pastors and teachers;" (Eph. 4: 11)

There are many fruits, which I am sure you are aware of. Catholicism's high numbers of members(mostly because of children born into the church) and duration of time on the earth mean nothing. The real test for the true Church are the fruits it brings forth.
The LDS Church is one of the fastest growing churches in the world. If it were around as long as the Catholic church was it would be a thousand times larger. Give it a little more time.