C. F. Keil and Franz Delitzsch on Psalms 70:4-5

Psa 70:4-5 ויאמרו instead of יאמרו is unimportant. But since the divine name Jahve is now for once chosen side by side with Elohim, it certainly had a strong claim to be retained in Psa 70:5. Instead of תּשׁועתך we have ישׁועתך here; instead of עזרתי, here עזרי. And instead of אדני יחשׁב לי we have here אלהים חוּשׁה־לּי - the hope is turned into petition: make haste unto me, is an innovation in expression that is caused by the taking over of the לי.