The word, "Contend" within the aforementioned Context means "to assert something as a position in an argument." It means to "make a Case for." The Holy Bible commands us to contend for our Faith, that is to make a case for the Gospel of Jesus Christ and assert that Christ is the Only True and Living Way. When the Lord Jesus commanded us to go into the world and make disciples of all nations, He didn't mean a "hit-and-run" affair. It is a Process that would sometimes require contending, arguing, debating and reasoning with people for as long as it takes to bring them to His Saving Knowledge (Acts 19:8-10). Let us take an example from the life and Ministry of Apostle Paul who was found in multiple instances contending for the Faith. He debated, argued and reasoned with the Jews, the Greeks, the Hellenists, a governor and a king (Acts 9:29, 13:14, 17:17, 18:4-6, 19). One thing we know about the Classical Greeks is that they were great thinkers and philosophers, yet Paul debated the greatest of them and proved Christ to them (Acts 14:1, 17:4,18). We learn from Paul that we don't just preach the Gospel but also convince or persuade when it is required (2 Tim. 4:2).
In our Evangelism, we would often encounter people who would question everything we are used to and everything that seems to be working for us in the Mission Field. Some of these people need more than our personal testimonies and even Miracles to convince them. Some may require historical and scientific proof that Christ lived, literally walked upon the face of the Earth and died. We often hear of and encounter many Muslims, Hindus, atheists and traditionalists who read the Bible for the purpose of finding loopholes and contradictions therein to disprove it. How can a Christian believer who is not committed to the study of the Word of God contend with such people? That is why the Holy Scriptures says that we perish without Knowledge (Hos. 4:6). And as a result, God would reject such a person from speaking for Him. This is very important because the Gospel would bring us before kings just as it brought Paul before Governor Felix (Acts 24:5) and King Herod Agrippa (Acts 26:1).
The following are some Basic Ways every Genuine Christian believer is expected to contend for the Faith:
1. PRAYER: (Ex. 17:8-16) This is the First Battleground for the souls of men and when we win the contention in prayer, contending in the natural becomes very easy.
2. KNOWLEDGE OF GOD'S WORD: (Rom. 10:17) How can we contend for the Faith if we don't have adequate Knowledge of God's Word? (2 Tim. 2:15). Adequate Knowledge of God's Word enables us to rightly divide the Word of Truth whenever we contend.
3. HISTORICAL AND SCIENTIFIC KNOWLEDGE: Christianity is not a licence for ignorance. As Christian believers, we need to understand to a great extent historical and scientific proof of Biblical events and prophecies. There are certain people whose conviction and Salvation will depend on it. This is not in any way endorsing mundane arguments that people often engage themselves in the name of defending Christianity. The Holy Bible warned us against such (1 Tim. 6:20, 2 Tim. 2:23-24, Tit. 3:9). We are commanded to avoid arguments that lead to quarrels and anger; rather, when we contend, we must do it with Inspiration from the Holy Spirit so that it will lead to the Salvation of those involved.