For I will have respect unto you, and make you fruitful, and multiply you, and {c} establish my covenant with you.

(c) Perform that which I have promised.

Wesley's Notes

26:9 Establish my covenant - That is, actually perform all that I have promised in my covenant made with you.

Matthew Henry's Concise Commentary

26:1-13 This chapter contains a general enforcement of all the laws given by Moses; by promises of reward in case of obedience, on the one hand; and threatenings of punishment for disobedience, on the other. While Israel maintained a national regard to God's worship, sabbaths, and sanctuary, and did not turn aside to idolatry, the Lord engaged to continue to them temporal mercies and religious advantages. These great and precious promises, though they relate chiefly to the life which now is, were typical of the spiritual blessings made sure by the covenant of grace to all believers, through Christ. 1. Plenty and abundance of the fruits of the earth. Every good and perfect gift must be expected from above, from the Father of lights. 2. Peace under the Divine protection. Those dwell in safety, that dwell in God. 3. Victory and success in their wars. It is all one with the Lord to save by many or by few. 4. The increase of their people. The gospel church shall be fruitful. 5. The favour of God, which is the fountain of all Good. 6. Tokens of his presence in and by his ordinances. The way to have God's ordinances fixed among us, is to cleave closely to them. 7. The grace of the covenant. All covenant blessings are summed up in the covenant relation, I will be your God, and ye shall be my people; and they are all grounded upon their redemption. Having purchased them, God would own them, and never cast them off till they cast him off.