"Elijah will come to give confidence to the faithful, and this Christ says; "Elijah will come and shall restore all things." (Matthew 17:11.) Therefore it is said, "In the spirit and power of Elijah." (Luke 1:17.) For St. John neither wrought signs nor wonders, as Elijah did. For "John," it is said, "did no miracle, but all things which John spoke of this Man were true." How then was it "in the spirit and power of Elijah"? That is, he will take upon him the same ministry. As the one was the forerunner of His first Coming, so will the other be of His second and glorious Coming, and for this he is reserved. Therefore, let us not fear. St. Paul has calmed the minds of the hearers and does not let them think any longer of the present things dreadful but worthy of thankfulness."
Homily on 2 Thess 2:10, Nicene and Post Nicene Fathers s. 1, v. 13, pp. 808-809.
"SAMSON IN THE OLD IS JOHN IN THE NEW"
Saint Irenaeus
The little boy, therefore, who guided Samson by the hand, pre-typified John the Baptist, who showed to the people the faith in Christ. And the house in which they were assembled signifies the world, in which dwell the various heathen and unbelieving nations, offering sacrifice to their idols. Moreover, the two pillars are the two covenants. The fact, then, of Samson leaning himself upon the pillars, [indicates] this, that the people, when instructed, recognized the mystery of Christ.