Verse 43 says, “And if your hand stumbles you, cut it off; it is better for you to enter into life maimed, than having two hands to go away into Gehenna, into unquenchable fire.” Here the stumbling one is changed from a person to a member of the believer’s fleshly body. The believers should not cause one another to stumble; neither should they be caused to stumble by their own fleshly members. This indicates how precious the believers are in the eyes of the Slave-Savior. They should all be fully preserved for Him. All the stumbling factors concerning the believers should be seriously dealt with.
In verse 43 “life” refers to eternal life, which the overcoming believers will enjoy in the coming kingdom. To inherit eternal life (Matt. 19:29) is to be rewarded in the coming age (Luke 18:29-30) with the enjoyment of the divine life in the manifestation of the kingdom.
“Gehenna” is the Greek equivalent of the Hebrew Ge Hinnom,valley of Hinnom. This was a deep and narrow valley near Jerusalem, the refuse-place of the city, where the bodies of criminals were cast, along with all kinds of filth. It was also called Tophet, or Topheth (2 Kings 23:10; Isa. 30:33; Jer. 19:13). Because of its continual fire, it became the symbol of the place of eternal punishment, the lake of fire (Rev. 20:15).
In Mark 9:43 “unquenchable fire” is in apposition to Gehenna. According to the context, it denotes a dispensational punishment, suffered by the defeated believers, such as being hurt of the second death in Revelation 2:11. As used in this verse, it does not refer to eternal perdition.
In 9:45 the Lord says, “And if your foot stumbles you, cut it off; it is better for you to enter into life lame, than having two feet to be thrown into Gehenna.” This is very similar to the word in verse 43. (In verses 44 and 46, some manuscripts insert, “Where their worm does not die, and the fire is not quenched.”)
In verse 47 the Lord continues, “And if your eye stumbles you, cast it out; it is better for you to enter into the kingdom of God with one eye, than having two eyes to be thrown into Gehenna.” To enter into the kingdom of God is to enter into the enjoyment of eternal life in the coming age.
Verse 48 says concerning Gehenna, “Where their worm does not die, and the fire is not quenched.” This word is a quotation from Isaiah 66:24.
Verse 49 says, “For everyone shall be salted with fire.” The purpose of this salting is to have the germs of corruption through sin killed and eliminated in order that sin-committing believers may be preserved (see Lev. 2:13; Ezek. 43:24).
The fire in Mark 9:49 is a refining fire (Mal. 3:2), a purifying, purging fire, as in 1 Corinthians 3:13, 15 (see Isa. 33:14), which will purge, in the kingdom age, the believers who commit sin and are unrepentant in this age, as a dispensational punishment. Even in this age God purges the believers through trials as by fire (1 Pet. 1:7; 4:12, 17). Dispensational punishment by fire in the coming age is in the same principle as God’s chastisement through sufferings as by fire in this age.
In verse 50 the Lord Jesus concludes, “Salt is good, but if the salt has lost its saltness, with what will you restore its saltness? Have salt in yourselves, and be at peace with one another.” Salt by nature is an element that kills and eliminates the germs of corruption. For the believers in Christ to lose their saltness means that they have lost their salting function. In such a case, they have become the same as earthly people and can no longer be distinguished from unbelievers.
The application of the Lord’s word here concerning salt differs from that in Matthew 5:13 and Luke 14:34. In Matthew and Luke, salt, portraying the believers’ influence upon the world, is for salting the corrupted world; salt here, in apposition to purging fire, is for the salting of sin-committing believers, even as God’s chastisements salt or purge sinning believers in this age. Hence, the believers should “have salt in themselves” so that they may be purified not only from sins but also from any divisive factor, such as that exhibited by the impetuous John in forbidding a brother who differed from him and in arguing for greatness. This purifying is that they may “be at peace with one another.” Such purging salt purges the believers’ speech as with grace (Eph. 4:29) that they may keep peace with one another (Col. 4:6). This way of speaking is very different from John’s word to the brother who differed from him. Therefore, the entire section at the close of chapter nine (vv. 38-50) presents the Slave-Savior’s teaching concerning the believers’ tolerance for the sake of unity.