I am not able to carry all this people alone is literally “I, I alone, I am not able to carry all this people.” The Hebrew pronoun for “I” occurs three times, once as an independent pronoun, to emphasize that Moses cannot take care of the Israelites by himself. The Hebrew verb for carry comes from the same root as the noun rendered “burden” in verse 11 (see the comments there).

The burden is too heavy for me is literally “because it is too heavy for me” (NET Bible). The pronoun “it” refers to the burden of taking care of the people. The Hebrew particle ki at the beginning of this clause may be a logical connector (“because”) or an emphatic marker, so another possible model here is “For sure, this burden is too heavy for me to carry!”

New Living Translation provides the following helpful model for this verse:

• I can’t carry all these people by myself! The load is far too heavy!

Quoted with permission from de Regt, Lénart J. and Wendland, Ernst R. A Handbook on Numbers. (UBS Helps for Translators). Miami: UBS, 2016. For this and other handbooks for translators see here .