חִזְק֣וּ וְאִמְצ֔וּ אַל־תִּֽירְא֥וּ וְאַל־תַּעַרְצ֖וּ מִפְּנֵיהֶ֑ם כִּ֣י ׀ יְהוָ֣ה אֱלֹהֶ֗יךָ ה֚וּא הַהֹלֵ֣ךְ עִמָּ֔ךְ לֹ֥א יַרְפְּךָ֖ וְלֹ֥א יַעַזְבֶֽךָּ׃ (פ)
Soyez forts et vaillants! Ne vous laissez effrayer ni intimider par eux! Car l’Éternel, ton Dieu, marche lui-même avec toi; il ne te laissera pas succomber, il ne t’abandonnera point!"
Rashi
לא ירפך means He will give you no looseness that you should be abandoned by Him (cf. Rashi on Deuteronomy 4:31).
Ibn Ezra
Be courageous and brave now that you know that God will stand with you in any place where you go to do battle. Moshe then said
Kli Yakar
For the Lord your God, He is the one who goes with you. We find the language of “going” in this portion in three aspects. For regarding Israel it is written, For the Lord your God, He is the one who goes with you, which implies that He holds your hand and guides you in the way you should go. But regarding Joshua it is written, The Lord, He is the one who goes before you, and regarding Moses it simply states, And Moses went without any support at all.
This is similar to what was said about Noah, who was of little faith, Noah walked with God (Genesis 6:9), meaning he needed support to sustain him. Similarly, regarding Israel it is written, For the Lord your God, He is the one who goes with you, because they needed support to sustain them in the fear of God. But regarding Joshua it says, The Lord, He is the one who goes before you, and he follows after Him, because he did not need as much support as Israel did. Nevertheless, he did not reach the level of the Patriarchs, about whom it says, God before whom my fathers walked, implying that the Divine Presence was behind them.
Moses reached this level, as it says, And Moses went, implying that he walked alone without any support at all. For one who walks after God has some support, but not like one who walks with God. For this reason, they said (Bava Batra 75a), “Moses’ face was like the face of the sun.” Just as the sun does not receive light from another celestial body, so too Moses shone with his own righteousness, while Joshua was like the moon that needs support from the sun’s light. But Israel was compared to the stars, whose light is minimal here and there, requiring much more support.
Astronomers have said that what the stars orbit in 70 years, the sun and moon orbit in one day. Similarly, the perfect ones like Moses and Joshua acquire their world in one day, gaining in one day the perfection that an average person cannot acquire except in 70 years — the average time that God has allotted for every person to acquire his perfection. And sometimes “gray hair has sprinkled on him, and he knows it not.”
This is similar to what was said about Noah, who was of little faith, Noah walked with God (Genesis 6:9), meaning he needed support to sustain him. Similarly, regarding Israel it is written, For the Lord your God, He is the one who goes with you, because they needed support to sustain them in the fear of God. But regarding Joshua it says, The Lord, He is the one who goes before you, and he follows after Him, because he did not need as much support as Israel did. Nevertheless, he did not reach the level of the Patriarchs, about whom it says, God before whom my fathers walked, implying that the Divine Presence was behind them.
Moses reached this level, as it says, And Moses went, implying that he walked alone without any support at all. For one who walks after God has some support, but not like one who walks with God. For this reason, they said (Bava Batra 75a), “Moses’ face was like the face of the sun.” Just as the sun does not receive light from another celestial body, so too Moses shone with his own righteousness, while Joshua was like the moon that needs support from the sun’s light. But Israel was compared to the stars, whose light is minimal here and there, requiring much more support.
Astronomers have said that what the stars orbit in 70 years, the sun and moon orbit in one day. Similarly, the perfect ones like Moses and Joshua acquire their world in one day, gaining in one day the perfection that an average person cannot acquire except in 70 years — the average time that God has allotted for every person to acquire his perfection. And sometimes “gray hair has sprinkled on him, and he knows it not.”