According to Thayer’s Greek Lexicon, this Greek word “[comes] from a verb which means to ‘stretch out the hand,’ thus it means to be stretched out.” In prayer, it conveys the idea of praying fervently, without ceasing and not relaxing in effort. This kind of prayer is a continuous prayer of straining and stretching to gain the answer.
Ektenos is found only twice in the New Testament. In Acts 12:5, it is used to describe the kind of prayer the church prayed for Peter, who was kept in prison. In this verse ektenos has been translated at least four different ways. The NIV and the RSV translate it as “earnestly praying” and “earnest prayer for him was made.” The KJV translates ektenos as prayer “without ceasing,” the NKJV as “constant prayer,” and the NASB as prayer being made “fervently.” I’m not sure which one of the translations is the most correct, but I would guess that they are all good translations. Therefore, if we put them all together, we may conclude that earnest prayer is constant, without ceasing, and fervent.
Particularly, in this case, we see that earnest prayer was made for Peter by the church. Certainly there is more power in corporate prayer, especially when it is united in earnestness. And such was the case here, for, as it happened, Peter was miraculously delivered (Read this amazing story in Acts 12: 5-17).
In the second occurrence, in 1 Peter 1:22, ektenos is used of how we are to love one another: “Since you have purified your souls in obeying the truth through the Spirit in sincere love of the brethren, love one another fervently with a pure heart” (NKJV).
Most translations, as it is here in the NKJV, render ektenos, as “fervently,” but the RSV translates it as “earnestly” and the NIV as “deeply.” So, putting it together, we are to love one another deeply, earnestly and fervently.
This love then is a love that is stretched out to the limits for others. It is a special kind of pure, heart-felt love given by the Holy Spirit that only believers possess. Moreover, I believe that there is a connection of this kind of love to earnest prayer. For it seems reasonable that when our prayers are earnest they are prayers of love from the heart of God.
This is what Duewel has said about fervency in prayer as it relates to love:
Fervency is born of love…Love is the very nature of God. His heart is aflame with love for us and for His world. The flame that burns in the heart of God will set your heart aflame if you will draw close enough to Him. His love radiates to your heart. As you pray, His love places on your heart deep concerns for the needs he sees and wants you to see. His love, as it imbues you, makes your prayer a sweet perfume before Him (Ps. 141:2). God’s love is dynamic. It adds love, desire, and zeal to your praying.