Dan
To be clear, the Love and Mercy of God was wrapped in the free gift of his Son Jesus, but when the Apostles evangelized they never started with articulating those themes.
A sample of Apostolic Preaching from
Acts 3
17 “Yet now, brethren, I know that you did it in ignorance, as did also your rulers. 18 But those things which God foretold by the mouth of all His prophets, that the Christ would suffer, He has thus fulfilled. 19
Repent therefore and be converted, that your sins may be blotted out, so that times of refreshing may come from the presence of the Lord, 20 and that He may send Jesus Christ, who was preached to you before,[a] 21 whom heaven must receive until the times of restoration of all things, which God has spoken by the mouth of all His holy prophets since the world began.
Much of the focus on the Mercy and Grace of God was much more expounded to those who already responded to the Good news by repenting.