But your iniquities have separated between you and your God, and your sins have hid his face from you, that he will not hear.

But your iniquities have divided between you and your God, and your sins have hid his face from you that he should not hear.

But your iniquities have been separating Between you and your God, And your sins have hidden The Presence from you, from hearing.

But your sins have come between you and your God, and by your evil doings his face has been veiled from you, so that he will give you no answer.

But your iniquities have made a division between you and your God, and your sins have concealed his face from you, so that he would not hear.

Sed iniquitates vestrae dissidium fecerunt inter vos et Deum vestrum; et peccata vestra operuerunt faciem ejus a vobis, ne audiat.

But your iniquities have made a separation. The amount of what is said is, that they cannot say that God has changed, as if he had swerved from his natural disposition, but that the whole blame lies with themselves; because by their own sins they, in some measure, prevent his kindness, and refuse to receive his assistance. Hence we infer that our sins alone deprive us of the grace of God, and cause separation between us and him; for what the Prophet testifies as to the men of his time is applicable to all ages; since he pleads the cause of God, against the slanders of wicked men. Thus God is always like himself, and is not wearied in doing good; and his power is not diminished, but we hinder the entrance of his grace. It will be objected, that men cannot anticipate God by deserving well of him, and that consequently he must do good to those who are unworthy. I reply, this is undoubtedly true; but sometimes the frowardness of men grows to such an extent as to shut the door against God's benefits, as if they purposely intended to drive him far away from them. And although he listens to no man without pardoning him, as we always bring before him supplication for the removal of guilt, yet he does not listen to the prayers of the wicked. We need not wonder, therefore, if the Prophet accuse the people of rejecting God's benefits by their iniquities, and rendering him irreconcilable by their obstinacy, and, in a word, of making a divorce, which drives away or turns aside the ordinary course of grace.

But your iniquities - That is, the sins which the prophet had specified in the previous chapter, and which he proceeds further to specify in this.
Have separated - The word used here (בדל bâdal) conveys the idea of division, usually by a curtain or a wall Exodus 26:33; Ezekiel 42:20. Thus the 'firmament' (רקיע râqı̂ya‛, "expanse") is said to have "divided" or "separated" (מבדיל mabedı̂yl) the waters from the waters Genesis 1:6. The idea here is, that their sins were like a partition between them and God, so that there was no contact between them and him.
And your sins have hid his face from you - Margin, 'Made him hide.' The Hebrew word here is in Hiphil, meaning 'to cause to hide.' Kimchi and Aben Ezra understand it as causing him to hide his face; Vitringa as hiding, his face. The metaphor, says Vitringa, is not taken from a man who turns away his face from one because he does not choose to attend to what is said, but from something which comes between two persons, like a dense cloud, which hides one from the other. And, according to this, the idea is, that their sins had risen up like a thick, dark cloud between them and God, so that they had no clear view of him, and no contact with him - as a cloud hides the face of the sun from us. A similar idea occurs in Lamentations 3:44 :
Thou hast covered thyself with a cloud,
That our prayers should not pass through.
But it seems to me more probable that the Hiphil signification of the verb is here to be retained, and that the idea is, that their sins had caused Yahweh to hide or turn away his face from their prayers from an unwillingness to hear them when they were so deeply immersed in sin. Thus the Septuagint, 'On account of your sins he has turned away his face (ἀπέστρεψε τὸ πρόωπον apestrepse to prosōpon) from you, so that he will not have mercy' (τοῦ μὴ ἐλεῆσαι tou mē eleēsai). It is universally true that indulgence in sin causes God to turn away his face, and to witchold mercy and compassion. He cannot pardon those who indulge in transgression, and who are unwilling to abandon the ways of sin (compare the notes at Isaiah 1:15).

His face - For פנים panim, faces, I read panaiv, his face. So the Syriac, Septuagint, Alexandrian, Arabic, and Vulgate. פני panai, MS. Forte legendum פני panai, nam מ mem, sequitur, et loquitur Deus; confer cap. Isaiah 58:14. "We should perhaps read פני panai; for מ mem follows, and God is the speaker." - Secker. I rather think that the speech of God was closed with the last chapter, and that this chapter is delivered in the person of the prophet. - L.

Like a partition wall dividing between them, so that they enjoy no communion with him in his worship and ordinances; which is greatly the case of the reformed churches: they profess the true God, and the worship of him, and do attend the outward ordinances of it; but this is done in such a cold formal way, and such sins and wickedness are perpetrated and connived at, that the Lord does not grant his gracious presence to them, but stands at a distance from them:
and your sins have hid his face from you, that he will not hear; or have caused him to hide himself; withdraw his gracious presence; neglect the prayers put up to him; deny an answer to them; or, however, not appear as yet for the deliverance and salvation of them, and bringing them into a more comfortable, prosperous, and happy condition.

hid--Hebrew, "caused Him to hide" (Lamentations 3:44).