Ephesians 6:22

"Whom I have sent unto you," saith he, "for this very purpose, that ye may know our state, and that he may comfort your hearts." This language he employs, not without a purpose, but in consequence of what he had been saying previously; "having girded your loins, having on the breastplate," &c., which are a token of a constant and unceasing advance; for hear what the Prophet saith, "Let it be unto him as the raiment wherewith he covereth himself, and for the girdle wherewith he is girded continually" (Ps. cix. 19); and the Prophet Isaiah again saith, that God hath "put on righteousness as a breastplate" (Isa. lix. 17); by these expressions instructing us that these are things which we must have, not for a short time only, but continually, inasmuch as there is continual need of warfare. "For it is said the righteous are bold as a lion." (Prov. xxviii. 1.) For he that is armed with such a breastplate, it cannot be that he should fear the array that is against him, but he will leap into the midst of the enemy. And again Isaiah saith, "How beautiful are the feet of him that bringeth good tidings." (Isa. lii. 7.) Who would not run, who would not serve in such a cause; to publish the good tidings of peace, peace between God and man, peace, where men have toiled not, but where God hath wrought all? If "faithful," he will tell no falsehood, he will in everything speak the truth:-"whom I have sent unto you for this very purpose, that ye might know our state, and that he may comfort your hearts." Amazing, transcendent affection! "that it may not be in the power," he means, "of them that would, to affright you." For it is probable that they were in tribulation; for the expression, "may comfort your hearts," intimates as much; that is, "may not suffer you to sink under it."

Tychicus is sent to give the Ephesians instructions not on his own accord. Rather he was sent by Paul for this purpose. Such was Paul's concern for them and his desire that they should be well informed.

Since I am not able to leave, chained as I am, to tell you, Tychicus, my dearest brother and faithful minister in the Lord, will make known to you all things. Thus you can safely believe him about all these matters. "Who do you think …

Saint John Chrysostom says the following: "that you may know about us," that is, that he may inform you of what is happening with me and not allow you to be disheartened on my account, since I am in afflictions and wear chains. And this …

He was a sincere Christian, and so a brother in Christ: he was a faithful minister in the work of Christ, and he was very dear to Paul, which makes Paul's love to these Christian Ephesians the more observable, in that he should now part with so good and dear a friend for their sakes, when his company and conversation must have been peculiarly delightful and serviceable to himself.