One of Rashi's 10 major explanation methods is the word meaning method. Rashi had 10 vehicles by which to explain word meaning. One word meaning submethod is the special connective word submethod. Examples of special connective words are if, then, when, because, also .... These special connective words typically have several usages. Rashi, in his comments, will indicate the varied usages of these words.

The word if can sometimes mean when. The difference between if and when is whether you expect the event you are talking about to happen. If you expect it to happen you use the word when; if you aren't sure you use the word if. There are about half a dozen verses where if means when: Ex20-22,Ex22-24,Lv02-14,Nu36-04,Gn28-20, Dt21-14. Let us carefully review one of these verses.

Verse Gn28-20:22 states And Jacob vowed a vow, saying, If God will be with me, and will keep me in this way that I go, and will give me bread to eat, and garment to put on, ... ...Then ...all that you shall give me I will surely give the tenth to you. Rashi comments on the underlined word if: A superior translation would be when. The verse should be translated as follows And Jacob vowed a vow, saying, when God will be with me, [And saves me from the perils of my brother, father-in-law and strange place], and will keep me in this way that I go, and will give me bread to eat, and garment to put on, ... ...Then ...all that you shall give me I will surely give the tenth to you.

Rashi's suggested translation of when versus if is motivated by a verse which explicitly states that God will be with me. Verse Gn28-15 explicitly states And, behold, I,God am with you, and will keep you in all places where you go, and will bring you back to this land; for I will not leave you, until I have done that about which I have spoken to you. Rashi's reasoning is that if God promised to be with Jacob then indeed Jacob's statement if you will be with me should be better translated as when you will be with me since it was certain to happen.

Sermonic points: Rashi teaches us etiquette. God had just promised to be with Jacob. This was a prophetic promise and had to be kept. Nevertheless Jacob uses the language if vs. when. Jacob teaches us the etiquette of receiving a promise from God. We should not brag that it is ours. Rather we should have an attitude that it is not coming to us and rely on God's providence to provide it. This priniciple of etiquette, not to hold people to their promises, but to act like we are undeserving of it, also applies to interpersonal relations.