Exegetically, in John 5:24, is ongoing possession of "eternal life" conditional on "hears" (once) and "believes" (once), or, do both present tense Greek verbs (participles) indicate required ongoing action (perseverance)?
Please consider the words of Jesus:
"24 Truly, truly, I say to you, whoever hears [present tense participle] my word and believes [present tense participle] him who sent me has [present tense; right now] eternal life. He does not come into judgment [present tense; right now], but has passed [perfect tense; from the past to present] from death to life." (ESV). John 5:24
Many are quick to emphasize the promise of "eternal life" in this verse. They may assert that "eternal life" cannot be lost because it lasts forever. While "eternal life" does last forever, it shouldn't be confused with possession of the state of "eternal life". Two illustrations may be helpful.
Suppose a man is gifted a $100 dollar bill; it's his and worth $100. If the bill is lost, he no longer has possession of it —the bill is still worth $100.00. It would be illogical to conclude he cannot lose it because the bill will always be worth $100.
Many employers offer life insurance to their employees while they remain with the company. It would be unreasonable for former employees to conclude that their life insurance will always remain in effect, even after leaving the company because it's called "life insurance".
In John 5:24, possession of eternal life is true ("has") while a person "hears" Christ's Word and "believes" in Him ("him who sent me"). To overlook these semantic qualifiers based on established rules of grammar is to reject God's inspired Word. A correct grammatical interpretation of Scripture is necessary for a correct doctrinal understanding. The Bible should define one's theological framework —not one's theology, the Bible.
The Apostle John, with great precision, grammatically constructed the words of Jesus as arranged in this verse. According to the book Greek Grammar Beyond the Basics (521-522; 1996), the two conditional participles used ("hears"; "believes"), best fall within the "customary (habitual or general) present" category . Wallace places the participle "believes" of John 3:16 inside this category (522). This category is defined by Wallace as, "the customary present is used to signal either an action that regularly occurs or an ongoing state" (page 521).
Please consider how Young's Literal Translation emphasizes the necessity to remain in ongoing belief:
Verily, verily, I say to you—He who is hearing my word, and is believing Him who sent me, hath life age-during, and to judgment he doth not come, but hath passed out of the death to the life. (John 5:24)
In the book, Life in the Son, Shank wrote the following:
Contrary to the assumption of many, John 5:24 does not present a privileged position, which, once attained, is forever irrevocable. Quite to the contrary, our Savior's Words depict a privileged position directly governed by the specific condition of habitually hearing and believing. Jesus declares that the happy circumstance of deliverance from present condemnation and of standing passed out of death into life is the privilege only of such as habitually hear His Word and believe the Father. It is only on the basis of a present hearing and believing that one shares the eternal life of God and enjoys deliverance from present condemnation and spiritual death. (Page 61; 1989).
A comparable passage to John 5:24 is probably John 10:27-29. This passage is used regularly to emphasize the doctrine known as "eternal security". While it's true that this passage provides security, it's also true that this security is conditional on perseverance. The "sheep" must "hear" and "follow" the Shepherd for eternal life.
27 My sheep hear [present tense] my voice, and I know [present tense] them, and they follow [present tense] me. 28 I give them [the group in verse 27 that is persevering in the present] eternal life, and they [the group in verse 27 that is persevering in the present] will never perish, and no one will snatch them [the group in verse 27 that is persevering in the present] out of my hand. 29 My Father, who has given them [the group in verse 27 that is persevering in the present] to me, is greater than all, and no one is able to snatch them [the group in verse 27 that is persevering in the present] out of the Father’s hand. (John 10:27-29)
A grammatical examination of John 5:24 indicates that Jesus requires perseverance ("hears" and "believes") to be saved. This conclusion is not an abstract theological deduction. All credible English translations grammatically affirm the necessity to persevere in the faith for John 5:24. The requirement to persevere is found in other passages of Scripture — especially within John's Gospel.
The Answer is Contained within the Verse
The Greek of John 5:24 (no major textual variants):
Ἀμὴν ἀμὴν λέγω ὑμῖν ὅτι ὁ τὸν λόγον μου ἀκούων καὶ πιστεύων τῷ πέμψαντί με ἔχει ζωὴν αἰώνιον καὶ εἰς κρίσιν οὐκ ἔρχεται ἀλλὰ μεταβέβηκεν ἐκ τοῦ θανάτου εἰς τὴν ζωήν.
An English Translation (NASB):
Truly, truly, I say to you, he who hears My word, and believes Him who sent Me, has eternal life, and does not come into judgment, but has passed out of death into life.
It is true the present tense can be used to reflect a variety of ideas, including what is noted in the question, a present, "ongoing action" or a "once" done idea. There are some key points to keep in mind, however, with this passage.
Argument from The Nature of the Participle
The participle is functioning in a substantive role. The nominative case definite article with the conjoined participles of like case (ὁ ... ἀκούων καὶ πιστεύων) are supplying the subject of the sentence. They are describing "he who..." or "the one who...." Regarding the participle, Daniel Wallace, in Greek Grammar Beyond the Basics notes some relevant points:
the point of reference [in time] is the controlling verb, not the speaker ... The present participle is used for contemporaneous time [to the controlling verb]. (This contemporaneity, however, is often quite broadly conceived, depending in particular on the tense of the main verb.)(614)
It should be noted that such a time reference is primarily with respect to adverbial uses of the participle, and less so of substantive ones. Yet since the verbal aspect still remains at some level even for substantive uses (620), some time aspect still remains.
Regarding Aspect (i.e. continuous, undefined, punctilliar, etc.):
In particular when a participle is substantival, its aspectual force is more susceptible to reduction in force.(615)
many substantival participles in the NT are used in generic utterances. The πᾶς ὁ ἀκούων (or ἀγαπῶν, ποιῶν, etc.) formula is always or almost always generic. As such it is expected to involve a gnomic idea. Most of these instances involve the present participle.(615)
However, though we do not have a πᾶς ("all ...") formula in this passage, Wallace states earlier in his discussion of the Gnomic Present:
the present participle, especially in such formulaic expression as πᾶς ὁ + present participle and the like, routinely belong here.(523)
So the gnomic idea is "especially" true with the πᾶς formulation, but is "routinely" true of many substantive present participles otherwise. The gnomic idea is:
a statement of a general, timeless fact. “It does not say that something is happening, but that something does happen.” The action or state continues without time limits.(523)
and in particular one "kind of gnomic" concept is
the use of the present in generic statements to describe something that is true any time (rather than a universal statement that is true all the time)(523)
To summarize, the present tense of these participles indicate:
- If they have any time relation still contained in them in their substantive role, it is controlled by the verb in the sentence.
- Given the context of the statement of the format of the assertion, are (it seems rather clearly) used in the routine way of making a gnomic, generic statement that is true at any time a person can be described by the two actions of the participles. That is, an assertion is being made that if any one hears and believes, then any particular one [blank]—where the [blank] in this case is rest of the verse that answers the "then" portion, which analysis follows below.
Argument from the Controlling Verb
The controlling verb is ἔχει ("has" or "is having"). Has what? ζωὴν αἰώνιον, "life everlasting." So the present tense of hear and believe in the participle indicates—if there is any time relation at all—to hearing and believing contemporaneously with "having life everlasting."
If one "has" (i.e. possesses) life everlasting, then that life referred to will not end; but also, if those who have this life are characterized by hearing and believing, then that means once they have truly heard and believed, that belief remains contemporaneously with the possessing of life everlasting received. So the belief never ends, nor the effect of having heard the word that brought that belief. So there would be a sense of perseverance/continuance forever to the participles, because of the relation to the time of the main verb, which persists forever.
However, this does not wholly rule out the "once" idea, either. This is because of the nature of the verbal idea of belief/faith. A belief is something that one enters into at some point. It is a trusting something. But trust/faith is a funny word, because if one later fails to trust/have faith in something, then it evidences that one really never had a true trust/faith in it before—because if one did truly trust/have faith in something, then nothing can pull one from that conviction, because one would continue to trust/have faith despite what might drive one away. So "once" entered into, faith should remain (persevere) if faith is true faith in the object the faith is placed in.
An example may help here. If a young child regularly jumps from a high point into his father's arms, who catches him without fail, one might say the child has faith in his father. But then an incident occurs in which an older brother convinces the child to jump to him, but the brother fails to catch the child, and the child is seriously hurt. After recovery, the father tries to get the child to jump to him. If the child does jump, he shows real faith in the father, for the adversity of the fall did not affect the faith; but if the child refuses, then it shows the child really never had faith in the father, but rather something else (possibly mere ignorance of the potential consequences, or a weak faith in the repeated successes that seemed fun at the time, or what not). A true faith in the father would have remained if the faith of the child had been focused there to begin with.
So in this passage, hearing "My word" (i.e. Jesus' relation to the Father and work for Him, v.17-23) conveys the message from the Father, "Him who sent Me," that must be believed. One enters into a true belief once, for that time one truly places trust in "Him who sent Me," and does so based on "My word," which also shows a trust of the messenger, Jesus, and His message. But continuing to hear what that message conveyed, and believe in the Father from it, is the result of the once entering into faith. Hence why the time frame of the everlasting life one possesses runs forever contemporaneously with the hearing/believing that initiated the faith that coincides with the everlasting life.
Argument Confirmed by Subsidiary Statement
The main verb expressing the possession of everlasting life is further clarified by the statement in the following clause, καὶ εἰς κρίσιν οὐκ ἔρχεται ("and into judgment does not come"). The verb ἔρχεται has the idea of movement to a place, destination, position, etc.. One "comes" via some movement from one thing to another thing. In this case, the one who hears and believes, possessing everlasting life, does not move into a place of judgment, or properly in context, the negative side of judgment, condemnation.
The verse is actually setting up for the contrast coming in John 5:29, where the resurrection of all people is going to come about, and some will be to life, and the rest to condemnation. The "good" that people can do to be part of the life there in v.29 is what is expresses here in v.24, to hear the Son and believe the Father. The former never "come" to the latter condemnation, but persist in the life gained.
So the contrast is the mutually exclusive experiences of either the possessing of life everlasting or the certain coming of one to condemnation. The one who has "once" believed (truly so) will continue to believe, for they possess the life everlasting and do not enter into judgment.
The Argument Confirmed by the Final Clause
The last statement of v.24 is ἀλλὰ μεταβέβηκεν ἐκ τοῦ θανάτου εἰς τὴν ζωήν ("but has passed from the death to the life"). It is a contrasting statement, but. The one hearing and believing "has passed," which is a perfect tense verb, showing a completed action with potentially present, continuing consequences. Those continuing consequences were already confirmed earlier in the verse, they passed to life, that continuing, everlasting life just noted.
However, what concerns us with your question is the use of the perfect tense here. That indicates a "point" in time in which the transition occurs (one at which it "completes"), and the continuing consequences begin. In other words, it emphasizes the "once" aspect of the entry into the continued state of belief, which state continues forever with that same life, the person not ever entering into condemnation.
The emphasis of the passage via the present participles is simply the gnomic idea that any who hear and believe have (1) life everlasting and (2) no forthcoming condemnation. However, real belief, by its particular nature, is something that must be entered into at a particular point in time "once," and then persists. So the word of the Son must be heard, and once that message conveyed by the Son from the Father is believed, the essence of the message heard remains, and the Father believed, and life gained, all of which will never end.