It is said about Shaddad ibne Aws (RA) that he once began to cry. People asked about his crying, and he replied: It is something I heard from Rasulullah (SAW) which makes me weep when I remember it. Rasulullah (SAW) had said: I fear for my people from Shirk (ascribing partners to Allah) and Hidden Desires. Shaddad (RA) says: I had asked: O Rasulullah! Would your people be guilty of idolatry after your death? Rasulullah (SAW) had replied: Yes (but) they will not worship the sun, the moon, a stone or an idol; but they will act for display (without sincerity). Hidden Desire is that one of them will start the day fasting, but when one of his desires will present itself to him; he will abandon his fast (and satisfy his desire). Source: Musnad Ahmed.
Let us not worship nicely so that others can see and praise us. Today, we wear beautiful clothes and jewelleries when attending an invitation or meeting a renowned person. Whereas, when the pious people of the past would get up for tahajjud prayer at night, they would wear their best clothes, put on the surma and decorate themselves nicely to stand in front of Allah.