"How should I witness to someone
who belongs to a denomination, who I suspect isn’t
trusting the Savior?"
The most effective way to
speak about the issues of eternity to a religious person
is not to get sidetracked from the essentials of salvation.
Upon hearing a person’s background, we may feel
an obligation to speak to issues such as infant baptism,
transubstantiation, etc. However, it is wise rather
to build on the points of agreement between the Bible
and the person’s denomination, such as the virgin
birth, the cross, and so on. One point of agreement
will almost certainly be the Ten Commandments. They
are the key to bringing any religious person to a saving
knowledge of the gospel.
After someone is converted
to Jesus Christ, the Bible will come alive and he will
be led into all truth by the indwelling Holy Spirit.
God’s Word will then give him light, and he will
forsake religious tradition as he is led by God. While
there are strong biblical arguments that may convince
unregenerate people that their church’s traditions
contradict Holy Scripture, there is a difficulty. Some
religious people hold the teachings of their church
to be on a par with, or of greater authority than, Holy
Scripture. It is therefore often futile to try to convince
them intellectually that their trust should be in the
person of Jesus Christ, rather than in their own righteousness
or in their church traditions. For this reason we should
aim at the conscience, rather than the intellect. Take
them through the Law of God (the Commandments) to show
that they are condemned despite their works, and strongly
emphasize that we are saved by grace, and grace alone,
rather than by trusting in our own righteousness or
If they are open to the
gospel, and are interested in what God’s Word
says in reference to their church’s teachings,
they will listen to Scripture. For example, in Matthew
8:14 we see that Peter (whom the Roman Catholic church
maintains was the first pope) was married, as were many
of the other apostles (see 1 Corinthians 9:5).