For if see comments on 4.11. With a transposition of clauses one may say “he hears us whenever we ask him; since we know this is true, we know also…” (Good News Translation).

He hears us in (or “concerning”) whatever we ask repeats verse 14b but in a shortened form. The qualification “according to his will” is implied here also. For whatever compare comments on 2.5.

Some adjusted renderings of the sentence may offer a better model; for example, ‘he listens to whatever (or all things) we ask,’ ‘he gives attention to (all) our words (or prayers),’ ‘he hears our words whenever we ask him something.’ Because this verse repeats verse 14b, further simplification is defensible when idiomatically preferable, such as “our requests are heard” (New English Bible), “he always listens to us” (Translators’ Translation).

We have obtained the requests made of him: the Greek verb form literally means “to have/possess/hold.” The present tense serves to show that this process occurs at the same time with the knowing of it. John means to say that, as soon as the believers realize that God hears them, they have/possess/hold already what they are praying for. This nuance, or shade, of meaning is in some languages best rendered by the perfect tense (compare Revised Standard Version), but often verb forms with the force of the English present tense will do. To shift to a future tense form is less advisable, because it means weakening John’s characteristic wording.

The verb form is in the active voice, but semantically speaking the role of the subject is not that of an agent. To bring this out some versions have such renderings as “the requests we have made of him are granted” (Goodspeed), “the things we ask for are ours” (New English Bible), ‘he is already giving us what we pray him for.’

The requests made of him is in the Greek literally “the requests we have requested of him,” again a combination of verb and related verbal noun; see comments on verse 10. The verb is in the perfect tense, referring to an act in the past that is still affecting the present. This tense serves here to mark a contrast with the preceding present tense. Therefore a rendering by a tenseless phrase such as ‘our requests/prayers (to him)’ is not recommended.

Quoted with permission from Haas, C., de Jonge, M. and Swellengrebel, J.L. A Handbook on The First Letter of John. (UBS Handbook Series). New York: UBS, 1972. For this and other handbooks for translators see here .