But I will {b} forewarn you whom ye shall fear: Fear him, which after he hath killed hath power to cast into hell; yea, I say unto you, Fear him.

(b) He warns them of dangers that presently hang over their heads, for those that come upon one suddenly make a greater wound.

Wesley's Notes

12:5 Fear him who hath power to cast into hell - Even to his peculiar friends, Christ gives this direction. Therefore the fearing of God as having power to cast into hell, is to be pressed even on true believers.

Scofield Reference Notes

Margin hell

See Scofield Note: "Mt 5:22".

Jamieson-Fausset-Brown Bible Commentary

5. Fear Him . Fear Him-how striking the repetition here! Only the one fear would effectually expel the other.

after he hath killed, &c.-Learn here-(1) To play false with one's convictions to save one's life, may fail of its end after all, for God can inflict a violent death in some other and equally formidable way. (2) There is a hell, it seems, for the body as well as the soul; consequently, sufferings adapted to the one as well as the other. (3) Fear of hell is a divinely authorized and needed motive of action even to Christ's "friends." (4) As Christ's meekness and gentleness were not compromised by such harsh notes as these, so those servants of Christ lack their Master's spirit who soften down all such language to please ears "polite." (See on [1646]Mr 9:43-48).

Matthew Henry's Concise Commentary

12:1-12 A firm belief of the doctrine of God's universal providence, and the extent of it, would satisfy us when in peril, and encourage us to trust God in the way of duty. Providence takes notice of the meanest creatures, even of the sparrows, and therefore of the smallest interests of the disciples of Christ. Those who confess Christ now, shall be owned by him in the great day, before the angels of God. To deter us from denying Christ, and deserting his truths and ways, we are here assured that those who deny Christ, though they may thus save life itself, and though they may gain a kingdom by it, will be great losers at last; for Christ will not know them, will not own them, nor show them favour. But let no trembling, penitent backslider doubt of obtaining forgiveness. This is far different from the determined enmity that is blasphemy against the Holy Ghost, which shall never be forgiven, because it will never be repented of.