1)
How could Moshe place the jar of Manna in front of the Aron "Lifnei Hashem" (see Sifsei Chachamim]), seeing as the Mishkan with its Keilim had not yet been built?
1.
Rashi and Rashbam: This Pasuk was actually said only after the Mishkan had been built, and it inserts it here because it belongs to the Parshah of the Manna. 1
1
In keeping with the principle 'Ein Mukdam u'Me'uchar ba'Torah'.
2)
What is the Torah referring to when it writes "LIfnei Hashem" in this Pasuk and "Lifnei ha'Eidus" in Pasuk 34?