So he departed - This clause should not be separated from the succeeding verse. The meaning is, "So he departed from him, and had gone a little way, when Gehazi bethought himself of what he would do, and followed after him."

And he said unto him - There is a most singular and important reading in one of De Rossi's MSS., which he numbers 191. It has in the margin לא ק that is, "read לא lo, not, instead of לו lo, to him." Now this reading supposes that Naaman did ask permission from the prophet to worship in Rimmon's temple; to which the prophet answers, No; go in peace: that is, maintain thy holy resolutions, be a consistent worshipper of the true God, and avoid all idolatrous practices. Another MS., No. 383, appears first to have written לו to him, but to have corrected it immediately by inserting an א aleph after the ו vau; and thus, instead of making it לא no, it has made it לוא lu, which is no word.

And he said unto him, (k) Go in peace. So he departed from him a little way.
(k) The prophet did not approve his act, but after the common manner of speech he bids him farewell.

And he said unto him,.... That is, the prophet said to Naaman:
go in peace: in peace of mind; be assured that God has pardoned this and all other transgressions:
so he departed from him a little way; about a mile, as the Targum, and so other Jewish writers; of this phrase; see Gill on Genesis 35:16, some say a land's length, that is, about one hundred and twenty feet; rather it was a thousand cubits, or half a mile.

Elisha answered, "Go in peace," wishing the departing Syrian the peace of God upon the road, without thereby either approving or disapproving the religious conviction which he had expressed. For as Naaman had not asked permission to go with his king into the temple of Rimmon, but had simply said, might Jehovah forgive him or be indulgent with him in this matter, Elisha could do nothing more, without a special command from God, than commend the heathen, who had been brought to belief in the God of Israel as the true God by the miraculous cure of his leprosy, to the further guidance of the Lord and of His grace.
(Note: Most of the earlier theologians found in Elisha's words a direct approval of the religious conviction expressed by Naaman and his attitude towards idolatry; and since they could not admit that a prophet would have permitted a heathen alone to participate in idolatrous ceremonies, endeavoured to get rid of the consequence resulting from it, viz., licitam ergo esse Christianis συμφώνησιν πιστοῦ μετὰ ἀπιστοῦ, seu symbolizationem et communicationem cum ceremonia idololatrica, either by appealing to the use of השׁתּחות and to the distinction between incurvatio regis voluntaria et religiosa (real worship) and incurvatio servilis et coacta Naemani, quae erat politica et civilis (mere prostration from civil connivance), or by the ungrammatical explanation that Naaman merely spoke of what he had already done, not of what he would do in future (vid., Pfeiffer, Dub. vex. p. 445ff., and J. Meyer, ad Seder Olam, p. 904ff., Budd., and others). - Both are unsatisfactory. The dreaded consequence falls of itself if we only distinguish between the times of the old covenant and those of the new. Under the old covenant the time had not yet come in which the heathen, who came to the knowledge of the true deity of the God of Israel, could be required to break off from all their heathen ways, unless they would formally enter into fellowship with the covenant nation.)