It is a proverb: A young man according to his way, even when he is old he will not depart from it.

Train up the child according to the tenor of his way, and when he is old he will not depart from it.

Give instruction to a youth about his way, Even when he is old he turneth not from it.

If a child is trained up in the right way, even when he is old he will not be turned away from it.

The proverb is: A youth is close to his way; even when he is old, he will not withdraw from it.

Train - Initiate, and so, educate.
The way he should go - Or, according to the tenor of his way, i. e., the path especially belonging to, especially fitted for, the individual's character. The proverb enjoins the closest possible study of each child's temperament and the adaptation of "his way of life" to that.

Train up a child in the way he should go - The Hebrew of this clause is curious: חנך לנער על פי דרכו chanoch lannaar al pi darco, "Initiate the child at the opening (the mouth) of his path." When he comes to the opening of the way of life, being able to walk alone, and to choose; stop at this entrance, and begin a series of instructions, how he is to conduct himself in every step he takes. Show him the duties, the dangers, and the blessings of the path; give him directions how to perform the duties, how to escape the dangers, and how to secure the blessings, which all lie before him. Fix these on his mind by daily inculcation, till their impression is become indelible; then lead him to practice by slow and almost imperceptible degrees, till each indelible impression becomes a strongly radicated habit. Beg incessantly the blessing of God on all this teaching and discipline; and then you have obeyed the injunction of the wisest of men. Nor is there any likelihood that such impressions shall ever be effaced, or that such habits shall ever be destroyed.
חנך chanac, which we translate train up or initiate, signifies also dedicate; and is often used for the consecrating any thing, house, or person, to the service of God. Dedicate, therefore, in the first instance, your child to God; and nurse, teach, and discipline him as God's child, whom he has intrusted to your care. These things observed, and illustrated by your own conduct, the child (you have God's word for it) will never depart from the path of life. Coverdale translates the passage thus: "Yf thou teachest a childe what waye he shoulde go, he shall not leave it when he is olde." Coverdale's Bible, for generally giving the true sense of a passage, and in elegant language for the time, has no equal in any of the translations which have followed since. Horace's maxim is nearly like that of Solomon: -
Fingit equum tenera docilem cervice magister
Ire viam, quam monstrat eques; venaticus, ex quo
Tempore cervinam pellem latravit in aula,
Militat in sylvis catulus. Nunc adbibe puro
Pectore verba, puer; nunc te melioribus ofter.
Quo semel est imbuta recens, servabit odorem
Testa diu.
Hor. Ep. lib. i., ep. 2, ver. 64.
"The docile colt is form'd with gentle skill
To move obedient to his rider's will.
In the loud hall the hound is taught to bay
The buckskin trail'd, then challenges his prey
Through the wild woods. Thus, in your hour of youth
From pure instruction quaff the words of truth:
The odours of the wine that first shall stain
The virgin vessel, it shall long retain."
Francis.

Train up a child (d) in the way he should go: and when he is old, he will not depart from it.
(d) Bring him up virtuously and he will continue so.

Train up a child in the way he should go,.... As Abraham trained up his children, and those born in his house, in the way of the Lord, in the paths of justice and judgment; which are the ways in which they should go, and which will be to their profit and advantage; see Genesis 14:14; and which is the duty of parents and masters in all ages, and under the present Gospel dispensation, even to bring such who are under their care in the nurture and admonition of the Lord, Ephesians 6:4; by praying with them and for them, by bringing them under the means of grace, the ministry of the word, by instructing them in the principles of religion, teaching them their duty to God and man, and setting them good examples of a holy life and conversation; and this is to be done according to their capacity, and as they are able to understand and receive the instructions given them: "according to the mouth of his way" (s), as it may be literally rendered; as soon as he is able to speak or go, even from his infancy; or as children are fed by little bits, or a little at a time, as their mouths can receive it;
and when he is old he will not depart from it; not easily, nor ordinarily; there are exceptions to this observation; but generally, where there is a good education, the impressions of it do not easily wear off, nor do men ordinarily forsake a good way they have been brought up in (t); and, however, when, being come to years of maturity and understanding, their hearts are seasoned with the grace of God, they are then enabled to put that in practice which before they had only in theory, and so continue in the paths of truth and holiness.
(s) "super os viae suae", Montanus; "ad os viae ejus", Schultens. (t) "Quo semel est imbuta recens servabit odorem testa diu", Horat. l. 1. Ep. 2. v. 69.

Train children, not in the way they would go, that of their corrupt hearts, but in the way they should go; in which, if you love them, you would have them go. As soon as possible every child should be led to the knowledge of the Saviour.

Train--initiate, or early instruct.
the way--literally, "his way," that selected for him in which he should go; for early training secures habitual walking in it.

6 Give to the child instruction conformably to His way;
So he will not, when he becomes old, depart from it.
The first instruction is meant which, communicated to the child, should be על־פּי, after the measure (Genesis 43:7 = post-bibl. לפי and כּפי) of his way, i.e., not: of his calling, which he must by and by enter upon (Bertheau, Zckler), which דּרכּו of itself cannot mean; also not: of the way which he must keep in during life (Kidduschin 30a); nor: of his individual nature (Elster); but: of the nature of the child as such, for דּרך נער is the child's way, as e.g., derek col-haarets, Genesis 19:31, the general custom of the land; derek Mitsrâyim, Isaiah 10:24, the way (the manner of acting) of the Egyptians. The instruction of youth, the education of youth, ought to be conformed to the nature of youth; the matter of instruction, the manner of instruction, ought to regulate itself according to the stage of life, and its peculiarities; the method ought to be arranged according to the degree of development which the mental and bodily life of the youth has arrived at. The verb חנך is a denominative like עקב, Proverbs 22:4; it signifies to affect the taste, חך (= חנך), in the Arab. to put date syrup into the mouth of the suckling; so that we may compare with it the saying of Horace, Ep. i. 2, 69: Quo semel est imbuta recens servabit odorem Testa diu. In the post-bibl. Hebrews. חנּוּך denotes that which in the language of the Church is called catechizatio; חנוך (לנער) ספר is the usual title of the catechisms. It is the fundamental and first requisite of all educational instruction which the proverb formulates, a suitable motto for the lesson-books of pedagogues and catechists. ממּנּה [from it] refers to that training of youth, in conformity with his nature, which becomes a second nature, that which is imprinted, inbred, becomes accustomed. Proverbs 22:6 is wanting in the lxx; where it exists in MSS of the lxx, it is supplied from Theodotion; the Complut. translates independently from the Hebrews. text.

Depart - Not easily and ordinarily.