A. Adjective.
Yâshâr (יָשָׁר, Strong's #3477), “upright; right; righteous; just.” This adjective occurs first in Exodus in the idiom “right in his eyes”: "[He] said, If thou wilt diligently hearken to the voice of the Lord thy God, and wilt do that which is right in his sight, and wilt give ear to his commandments, and keep all his statutes, I will put none of these diseases upon thee, which I have brought upon the Egyptians: for I am the Lord that healeth thee” (Exod. 15:26). Its usage is infrequent in the Pentateuch and in the prophetical writings. Predominantly a poetic term, yâshâr also occurs idiomatically (“to do what is right”) in the historical books; cf. 1 Kings 15:5: “Because David did that which was right in the eyes of the Lord, and turned not aside from any thing that he commanded him all the days of his life, save only in the matter of Uriah the Hittite.”
The basic meaning is the root meaning “to be straight” in the sense of “to be level.” The legs of the creatures in Ezekiel’s vision were straight (Ezek. 1:7). The Israelites designated an easy road for traveling as a “level road.” It had few inclines and declines compared to the mountain roads (cf. Jer. 31:9: “They shall come with weeping, and with supplications will I lead them: I will cause them to walk by the rivers of water in a straight way, wherein they shall not stumble: for I am a father to Israel, and Ephraim is my firstborn”).
Yâshâr with the meaning “right” pertains to things and to abstracts. Samuel promised himself to instruct God’s people in “the good and the right way” (1 Sam. 12:23). Nehemiah thanked God for having given just ordinances: “Thou camest down also upon mount Sinai, and spakest with them from heaven, and gavest them right judgments, and true laws, good statutes and commandments” (Neh. 9:13). Based on His revelation God expected His people to please Him in being obedient to Him: “And thou shalt do that which is right and good in the sight of the Lord: that it may be well with thee, and that thou mayest go in and possess the good land which the Lord sware unto thy fathers” (Deut. 6:18).
When yâshâr pertains to people, it is best translated “just” or “upright.” God is the standard of uprightness for His people: “Good and upright is the Lord: therefore will he teach sinners in the way” (Ps. 25:8). His word (Ps. 33:4), judgments (Ps. 19:9), and ways (Hos. 14:9) reveal His uprightness and are a blessing to His people. The believer follows Him in being “upright” in heart: “Be glad in the Lord, and rejoice, ye righteous; and shout for joy, all ye that are upright in heart” (Ps. 32:11; cf. 7:10; 11:2). In their daily walk they manifest that they are walking on the narrow road: “The wicked have drawn out the sword, and have bent their bow, to cast down the poor and needy, and to slay such as be of upright conversation” (Ps. 37:14). The “just” are promised God’s blessing upon their lives (Prov. 11:10-11).
Finally, yâshâr is also the abstract “rightness,” especially when the Hebrew word has the definite article (hayyâshâr, “the right”): “Hear this, I pray you, ye heads of the house of Jacob, and princes of the house of Israel, that abhor judgment, and pervert all equity [all that is right]” (Mic. 3:9).
The Septuagint translations are: arestos (“pleasing”); dikaios (“upright; just; righteous”); euthes (“upright”); and euthus (“straight”).
B. Verb.
Yâshar (יָשַׁר, Strong's #3474), “to be straight, be smooth, be right.” This verb, which occurs rarely has many derivatives in the Bible.
In Akkadian the verb isharu signifies “to be straight, bring in order,” and the noun misharum denotes justice and an upright way of life. The Hebrew word has many related words in other Semitic languages (Phoenician, Ugaritic) and even in Egyptian.
One occurrence of the verb is in 1 Chron. 13:4: “And all the congregation said that they would do so: for the thing was right in the eyes of all the people.” In this usage yâshar has the sense of being pleasing or agreeable. In Hab. 2:4 the word implies an ethical uprightness.
C. Nouns.
Yôsher (יֹשֶׁר, Strong's #3476), “straightness.” This noun occurs about 15 times. One occurrence is in Prov. 2:13: “Who leave the paths of uprightness, to walk in the ways of darkness.” Other nouns occur less frequently. Yishrah means “uprightness” and occurs once (1 Kings 3:6). The noun yeshurun is an honorific title for Israel (Deut. 32:15; 33:5). Mishor means “level place, uprightness.” In 1 Kings 20:23 mishor refers to “level country”; in Isa. 11:4 the word refers to “uprightness”: “… And reprove with equity for the meek of the earth.…”